Been reading tons of posts about what could cause the rough idle and stalling when cold. That's what I'm dealing with. MIL on, codes for MAF, fuel trim and O2 sensor. Another shop replaced the MAF, no change. I did plugs, cleaned TB and replaced fuel filter, no change. Problem seems a little better ...

I've been through this. Sounds like your mechanic is just following the recommended actions displayed on his diagnostic tool. I don't think that's going to do it in this case. He needs to dive deeper - which involves watching and understanding live data, and probably a smoke test. Quite a few mecha...