I'm a TRE and have so far not found any problems with doing checks for other JAA pilots.
You have clearly led a rather sheltered life since being authorised, then. There are a number of JAA member states whose national law requires that all entries in licences are made by the NAA and not by the individual TRE. And just what use do you suppose a CAA form would be in getting a type rating entered on an Italian issued licence??
bliss177 - You must, somehow, obtain from the TRE who conducted the test a copy of his letter of authorisation. Keep calling BAe at Woodford - they haven't gone out of business......yet.