As far as I can see the latest firmware available for a Mavic Pro is still v01.04.0500 from 2018/09/03.
Maybe you're talking of a separate flysafe update? That's not firmware so be clear if that's what you mean.
Yep not much anyone can do if you have nothing left to show.
Try to get in contact with the tour op and see if there's a way you can get your backpack found and shipped to you, might be a while but...