Hello Cliodhna Fullam,
Welcome to Microsoft Community.
I understand the inconvenience this must be to your husband.
So please allow me to share the download address of the driver and firmware package for Surface Pro 8 here:
Download Surface Pro 8 Drivers and Firmware from Official Microsoft Download Center
I'm not sure if the driver download package your husband obtained came from here
After you have finished downloading, you will notice that this is an msi file that can be run directly when you double-click it. After installing the driver and firmware package, restart your husband's Surface Pro 8 and make sure the Typer Cover works properly.
If Typer Cover still doesn't work on this Surface Pro 8, please refer to the instructions in "Confirm connectivity" in the support link below and try entering UEFI to confirm that Typer Cover is connected properly:
Troubleshoot Surface Type Cover or Keyboard - Microsoft Support
If you find Typer Cover completely unusable in UEFI, it may be damaged and in need of repair. You and your husband may need to return to your country after your vacation and then contact your local Surface technical support team to send them the device:
How to get service or repair for Surface - Microsoft Support****
I wish you all the best.
Best Regards,
Mitchell | Microsoft Community Support Specialist