Certainly not suggesting that one retain a solicitor for the purpose. If you read what I wrote, I specifically suggested putting this issue "on the list of things".
If this is acrimonious, there will be a long list of them and putting them on a list to be dealt with is a smart thing. If this is not acrimonious, then there is nothing to worry about in the first place as OP and the soon to be former spouse can simply deal with the cancellation and refund as it ought to be.