How to Allow a Kiosk-Mode Computer to Access a Shared HTML File on the Network?

I’m trying to set up a kiosk computer in Assigned Access mode, and it needs to open a specific HTML file located on a shared folder on a Windows server. The requirements are:

The kiosk computer should only have access to this file.
The file should not be shared with “everyone” for security reasons.
Only specific users should have access.
When I access the file with a regular user account, it prompts for permissions, but works after granting them. However, in kiosk mode, trying to access the same file results in an error:

File Not Found
The file might have been moved, edited, or deleted.
ERR_FILE_NOT_FOUND

The computer is not domain-joined (since kiosk mode creates a local user by default), which I suspect might be causing the issue due to permissions

My question is:

How can I configure permissions so the kiosk computer can access the file without compromising security?
Is it possible to add the kiosk computer to the shared folder’s permissions to resolve this issue?

Any guidance or solutions would be greatly appreciated!