2017 Tahoe with very rough idle

[dksharp]

We have a 2017 tahoe with 155K miles on it. It began idling very rough a few weeks ago. It had bank 2 sensor 1 O2 sensor bad so I replaced it. Still not better. I ended up replacing all the spark plugs and wires. No change. Cleaned the MAS air sensor. No change. 3 mechanics have looked at it. Bank 1 sensor 1 O2 indicator was delayed so replaced that one. Chevrolet recommends changing motor mounts which are worn out. We will but not at this time. 3rd mechanic says there is a technical service bulletin that mentions a lifter issue and possible camshaft issues. This mechanic thinks one of the lobes is rounded on the cam and causing this issue. His recommendation is to trade it in. I personally think it is a vacuum leak. Does anyone have any feedback on this top or know the vacuum system well?