VS130 VHF Failure
 

Virgin A330-300 reported VHF issues and London refused to accept them.

Ended up in Cardiff

Seems a bit silly in these days of CPDLC and accepted radio issue procedures ?

CPDLC doesn't work very well in the terminal environment, and it's far easier to accommodate NORDO aircraft at a low-traffic regional airport than at one of, if not the busiest part of airspace in Europe.

Was this a Neo by chance ( know Thales issue on them ) that was not yet modified. ?
Extremely rare to have a technical issue on VHF on a modern airliner (other than finger trouble) .But very understandable that EGLL APP refused it , Too much traffic to safely accommodate it .