Old-Duffer
as ever, you are right on the medal/cross problem.
The last DFM was indeed - IIRC - awarded to a Chinook crewperson in GW I, who had already been awarded an AFM - also one of the last. I think he's been advised - TTN may wish to comment - that the (monetary) worth of that group is extremely high!
And of course, there's no reason why decisions cannot be reversed; after all, we've got the BEM back after some years of MBE only........