Trying to flash P5QL-VM-EPU rom onto Essentio CM5570

[withalligators]

Hey guys, have an older ASUS Essentio CM5570 775 socket prebuilt. Not my main rig, but I'd like to play around with OCing it and putting a 771 modded CPU in there and maybe use it as a MAME rig. 

Even though the MB is a PQ5L-VM-EMU (as hidden by a sticker) it's got a different BIOS and won't let me flash to the retail board version that has OC features. 

There is a guide here where somebody documents how they did it (create DOS bootable USB with HP tools and Win98, put Afudos engineering edition and BIOS on there, etc.)

Problem is, this far down the line, I can't seem to find the "engineering edition" anywhere. 

I've made DOS bootable USBs using the HP tools with WIn 98 as well as with RUFUS and FreeDOS, and using AFUDOS 2.29ES and 3.36. I always get 

ERROR: Unable to open ROM file

I've downloaded the 0601 BIOS multiple times from ASUS and WImsBIOS. I've tried older BIOSes as well but can't seem to get past that error. 

When I run AFUDOS in DOS it lists the version used and in parentheses says ASUS v2 making me think it's an ASUS version that won't let me flash the board with a different ROM. 

Can anyone help or point me towards the file I need or an alternative BIOS flasher for AMI BIOSes that can override whatever check it needs to?

Cheers in advance