I would never in a million years provide them cash. They could just say they never go the reimbursement from me at a time when they are angry. People do the most ridiculous things when they are angry.
Edited to say: I could just write them a cheque and hand it to them the following Monday. That would be quite easy. Then they could have the reimbursement asap and I am in control of it, no cheques have to be changed and I can keep better track of it with the memo on my cheque. You just gave me a who new system. Awesome!!!! Thanks.