download the small exe file. not the EXE one. then create a bootable
USB FreeDos from Rufus. Copy exe to root.
Try flashing again and add this switch: -rebrand
That is the switch to convert from an OEM BIOS to a standard BIOS. It may allow it to overlook the issue of not recognizing a current BIOS version. If that does not work then I would suggest clearing NVRAM via jumper on the system board. If none of that works then the boards may need to be replaced. I suspect someone force flashed the wrong BIOS on these servers.
Also, try these switches
-brandname
And be sure to choose 0 for poweredge. Selecting 1 will designate it as a PowerVault.
Thanks