I'm pretty sure you'll find by Certificate of Competence they mean the Blue Book you have as an RAF ATCO - being TG9 something she won't have.
However - I'm just off to the pub with an R/T examiner who works in the tower at that little airport the other side of the M4
Drop me her contact details, I'll pass them on and I'm pretty sure he'll sort out an R/T licence for her.