I think the amount of information required to make a MR transfer varies my airline; are you sure they ask just for the number? I believe most require a surname at least. There is one MR transfer partner which will accept transfers even if the surnames do not match, but I would not like to say which publicly.
I had difficulties tranferring to Asia Miles as their system had managed to put a space into my name; I had to contact Asia Miles directly to have the name on file changed before the transfer would work. Therefore I doubt you can transfer your MR to any Asia Miles account you wish.
Trial and error if your friend; if a transfer doesn't work it will be rejected and the points will return to your account; you will not lose them.