Update from my end, finally got my 4090 back from B-Hawk Gaming today, fitted with new connector and all working fine. They did a great job of the soldering, very quick turnaround and sent pictures all the way through the process, total cost was £114.50 including return shipping. So for now the 4090 is up and running again. Have sent invoices over to CableMod and they are gonna put the refund in my PayPal account in the next 2-4 days.
Can't complain at all really with the service from B-Hawk Gaming and Cablemod, both did a great job.
Only thing is now I just don't trust it not to happen again, really considering selling it on and switching to a 7900XTX but running a 32:9 ultrawide I need all the performance I can get tbh. Plus I guess the resale value of an opened 4090 with no warranty remaining isn't gonna be all that great is it. Decisions decisions lol