Sorry to say it, but you're doing basically all you can.
Virgin Mobile don't operate the radio network so all they can do is ask EE about local faults (you've already done this) and relay to you what they say (which is probably no more than you've found out).
If you were a customer of EE directly, you may be able to ask their tech-C/S directly.. but I'm doubtful they'd let on anymore, and your supplier is Virgin not EE.
EE's own customers will also be affected by this (although they'll have additional 4G coverage and WiFi calling to mitigate the problem), so I'm sure they'll be restoring service as soon as possible.
Compensation will be a matter between you and Virgin, but they may well argue that it's only coverage in one area that's affected and your phone is working fine elsewhere.