I too got city and guilds in 80's, but my certificate got lost.
After 6 months of battling with city and guilds, loads of phone calls
they took the 34.00 and then i heard nothing, they couldn't be bothered to send a letter to say that they couldn't find a copy of it.
Eventually had to get a statutory declaration off a solicitor.
And now i havent a clue whats going on about tra, even though i applied under pathway A or B will they put me under pathway D
as i only have a statutory declaration. I just feel well sick at the moment

Have a feeling tra will be returned now!! took ages to do as well, its been a u turn that came right out of the blue