The problem is in the ATIRadeon9700GLDriver executable. More precisely, execute the following on your various Leopard distributions:
$ file /System/Library/Extensions/ATIRadeon9700GLDriver.bundle/Contents/MacOS/ATIRadeon9700GLDriver
This will tell you what kind of executable code (ppc, i386 or both) is present in the executable.
The problem is in the GL framework for the ATIRaden97000, not the ATIRadeon9700.kext itself. We've proven that the .kext has i386 executable code, so it's not the problem. The problem is they've removed i386 code from the Radeon9700GLDriver, hence the reason why the driver can't talk to the GL framework and why QE/CI doesn't get enabled.
By executing the previous command to earlier distributions we might find an early enough version of the driver that still has some i386 code but yet implements the new open GL framework.
Until you've proven that your GL framework does have i386 code you're basically shooting blanks and loosing your time.
Thanks for the work, man!