when
@dgsga looked at my IOReg and saw the absence of the DROM, he said to check again for a DROM error entry in my system log. none there.
having said that, without the DROM loading, my apple TB monitor including camera and mic is working fine. that's the only TB device I have and no plans to add more.
in about this Mac--system report--Thunderbolt, does your Thunderbolt bus appear?
I've been doing lots of experimenting with flashing my AR AIC, and now with the non-flash approach, and I have found that often I have needed to reset CMOS (then reset BIOS and unlock MSR) for the thunderbolt bus to appear and to get the TB tree to populate properly in IOReg. other times when when TB is missing, I just need to shut power off to the PSU for a few seconds, then restart, then often followed by a "warm boot".