I don't see why not. After all, CD32 versions of Chuck Rock & Last Ninja, Premiere, more others already use ECS disk images & a custom loader that removes protection, fixes blitwaits... Rings a bell?
The only problem with reusing whdload slaves "as is" would be the lack of keyboard on standard CD32 setup (I have a A2000 keyboard that connects to the CD32 but most users don't).
Button 1 & 2 would work nice, but you won't be able to pause by pressing "P", "ESC", "space bar" whatever (so long for Desert Strike w/o keyboard).
OR the slaves would need to be modified to be able to read joypad buttons to simulate the keyboard, each and every one, one by one (no generic processing possible here).
OR the tool could be able to "inject" a keyboard event through the joypad reads: read joypad during vblank, and somehow "forward" the utility buttons (pause, green ...) to the keyboard handler. Don't know if it's possible on a real amiga, or Bert would already have done it (or Bert already did it for whdloadcd32 ??)