I have a asus laptop with Ati Mobility HD 2600 working with internal LCD on 1024x768.
and then i tested your RadeonDumpL and RadeonPCI.kext.
I think there is a bug with IOGraphicsFamily.kext to find Internal LCD's edid.(Maybe the bug is i2c command)
in my case,
without Natit and ATINDRV I found the edid for my CRT not Internal LCD(1024x768)
with Natit and ATINDRV I also found the edid for my CRT(QE supported)
Found a device of class RadeonPCI: IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/P0P1@1/IOPCI2PCIBridge/VGA@0/RadeonPCI
it matched on name "display"
Card device id: 0x9581
Start I2C dump
EDID at DDC 0:
EDID at DDC 1:
Read EDID at DDC 1 failed
EDID at DDC 2:
Read EDID at DDC 2 failed
EDID at DDC 3:
Read EDID at DDC 3 failed
Sorry for my english