Yes and no, RadeonHDs don't work out of the box in PowerMac11,2. Proper init code needs to be written/fixed. So it's not the case: cards works in Sa,460, it will work in G5 PCIe.

btw. I'll have current version of MorphOS on G5 PCIe with RadeonHD card during
https://chal.pl/amiparty-xxii/general-information-english-version/