Kaitlyn is not a medieval name; it is a modern day American mispronunciation and misspelling of the Irish Gaelic name CaitlĂn (it should be pronounced like 'Cathleen'). It is derived from Catherine.
We need more information:
a) How do you spell your fiance's surname?
b) How is your fiance's surname spelled on your visa?If the answers to questions a and b were different then yes.
That would not necessarily void the contract. If there is not any doubt as to who the parties are, it will be enforced. If fraud were involved, the contract could be enforced and criminal charges...
Aside from the most common traditional deposit investments you can have in a bank (checking, savings, and certificate of deposits), there are other potential higher-yielding non-deposit investments...