A non UK Examiner cannot sign your licence for Revalidation by Experience. Only a UK Examiner or UK FI with FCL945 privileges can do that. Any authorisation to sign UK licences is for revalidation by Prof Check.
CAA Website:
Revalidation by experience
If you are revalidating your SEP by experience and are flying in a European Member State, please note that a Certificate of Revalidation held on a licence issued by the UK cannot be signed by a non-UK EASA examiner.
SEP revalidation by experience can be signed in a UK issued licence by an examiner holding a valid UK issued Part-FCL examiner certificate or a Flight Instructor with the privileges of FCL.945.