Your setup would be neat if you'd just replace the cheap customized locked ZTE Maxis 4G dongle which they supplied.
Just get one online instead which is unlocked which comes with stock firmware.

Just make sure you get a "hostless" 4G dongle which doesn't require additional software to connect.

I've used the backup Maxis SIM with a Huawei E3372H Hi-Link that has its own webgui and it worked flawlessly.

You can take a look here how I discovered Maxis ZTE works with other device: Ditch ONU, use GPON SFP on Business Grade Router

Yes, just set your Windows Computer Name (Hostname)

in Linux, you can send DHCP Option 12 to dongle without change Hostname

4gda to the rescue : 4pda.to/forum/index.php?showtopic=968586&st=240

They have the firmware files for MF833v