1. Your wife must contact the hospital in which she had worked. I suggest she do this by (i) Telephone Call (ii) Backed up by email or by letter. But, record what was said and to whom.Glad to see it worked out for you @Ada2019 .
My wife is in a similar situation - she is missing 10 years service from a previous role in a hospital which haven't transferred to her current role (in a local authority).
Can i ask, how did you get the confirmation letters from previous employers?