'Operation not permitted' when using modprobe/insmod

I'm trying to install a driver module for a dedicated PCIe board. I'm using the same OS and kernel versions stated in the datasheet but am getting the Operation not permitted error when adding the module to the kernel.

Things I've tried:

1. Disabling Secure Boot and other Bios options that might interfere. I've also used mokutil --sb-stat which returns SecureBoot disabled.

2. Signing the module and using MOK management during boot (as explained here).

3. Running modprobe/insmod as root.

4. lsmod to check if module was already added somehow, which it isn't.

Edit: The sudo modprobe -vvv output is as follows:

modprobe: INFO: ../libkmod/libkmod.c:365 kmod_set_log_fn() custom logging function 0x559b6c01fc70 registeredmodprobe: DEBUG: ../libkmod/libkmod-index.c:755 index_mm_open() file=/lib/modules/5.13.0-28-generic/modules.dep.binmodprobe: DEBUG: ../libkmod/libkmod-index.c:755 index_mm_open() file=/lib/modules/5.13.0-28-generic/modules.alias.binmodprobe: DEBUG: ../libkmod/libkmod-index.c:755 index_mm_open() file=/lib/modules/5.13.0-28-generic/modules.symbols.binmodprobe: DEBUG: ../libkmod/libkmod-index.c:755 index_mm_open() file=/lib/modules/5.13.0-28-generic/modules.builtin.alias.binmodprobe: DEBUG: ../libkmod/libkmod-index.c:755 index_mm_open() file=/lib/modules/5.13.0-28-generic/modules.builtin.binmodprobe: DEBUG: ../libkmod/libkmod-module.c:556 kmod_module_new_from_lookup() input alias=CsE16bcd, normalized=CsE16bcdmodprobe: DEBUG: ../libkmod/libkmod-module.c:562 kmod_module_new_from_lookup() lookup modules.dep CsE16bcdmodprobe: DEBUG: ../libkmod/libkmod.c:598 kmod_search_moddep() use mmaped index 'modules.dep' modname=CsE16bcdmodprobe: DEBUG: ../libkmod/libkmod.c:403 kmod_pool_get_module() get module name='CsE16bcd' found=(nil)modprobe: DEBUG: ../libkmod/libkmod.c:411 kmod_pool_add_module() add 0x559b6d4f1d50 key='CsE16bcd'modprobe: DEBUG: ../libkmod/libkmod-module.c:202 kmod_module_parse_depline() 0 dependencies for CsE16bcdmodprobe: DEBUG: ../libkmod/libkmod-module.c:589 kmod_module_new_from_lookup() lookup CsE16bcd=0, list=0x559b6d4f9410modprobe: DEBUG: ../libkmod/libkmod.c:500 lookup_builtin_file() use mmaped index 'modules.builtin' modname=CsE16bcdmodprobe: DEBUG: ../libkmod/libkmod-module.c:1760 kmod_module_get_initstate() could not open '/sys/module/CsE16bcd/initstate': No such file or directorymodprobe: DEBUG: ../libkmod/libkmod-module.c:1770 kmod_module_get_initstate() could not open '/sys/module/CsE16bcd': No such file or directorymodprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_pcsp mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_usb_audio mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=cx88_alsa mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_atiixp_modem mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_intel8x0m mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_via82xx_modem mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=bt87x mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=cx88_alsa mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=saa7134_alsa mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_atiixp_modem mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_intel8x0m mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_via82xx_modem mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_usb_audio mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_usb_caiaq mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_usb_ua101 mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_usb_us122l mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_usb_usx2y mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_cmipci mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_pcsp mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=snd_usb_audio mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=bonding mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=dummy mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1404 kmod_module_get_options() modname=vt mod->name=CsE16bcd mod->alias=(null)modprobe: DEBUG: ../libkmod/libkmod-module.c:1760 kmod_module_get_initstate() could not open '/sys/module/CsE16bcd/initstate': No such file or directorymodprobe: DEBUG: ../libkmod/libkmod-module.c:1770 kmod_module_get_initstate() could not open '/sys/module/CsE16bcd': No such file or directorymodprobe: DEBUG: ../libkmod/libkmod-module.c:750 kmod_module_get_path() name='CsE16bcd' path='/lib/modules/5.13.0-28-generic/kernel/drivers/misc/CsE16bcd.ko'modprobe: DEBUG: ../libkmod/libkmod-module.c:750 kmod_module_get_path() name='CsE16bcd' path='/lib/modules/5.13.0-28-generic/kernel/drivers/misc/CsE16bcd.ko'insmod /lib/modules/5.13.0-28-generic/kernel/drivers/misc/CsE16bcd.ko modprobe: DEBUG: ../libkmod/libkmod-module.c:750 kmod_module_get_path() name='CsE16bcd' path='/lib/modules/5.13.0-28-generic/kernel/drivers/misc/CsE16bcd.ko'modprobe: INFO: ../libkmod/libkmod-module.c:892 kmod_module_insert_module() Failed to insert module '/lib/modules/5.13.0-28-generic/kernel/drivers/misc/CsE16bcd.ko': Operation not permittedmodprobe: ERROR: could not insert 'CsE16bcd': Operation not permittedmodprobe: DEBUG: ../libkmod/libkmod-module.c:468 kmod_module_unref() kmod_module 0x559b6d4f1d50 releasedmodprobe: DEBUG: ../libkmod/libkmod.c:419 kmod_pool_del_module() del 0x559b6d4f1d50 key='CsE16bcd'modprobe: INFO: ../libkmod/libkmod.c:332 kmod_unref() context 0x559b6d4f14e0 released`

Appreciate any help! Thanks!