Would air intake hose not connected influence upper plenum/catlytic converter issues?

sounds like a misdiagnosed on the plugged cats, and maybe the plenum ,although they are plastic and do crack, unhooked filter tube should not damage a cat, if it ran strong before.Unhooked will throw it in limp mode, or factory presets and light will come on.without tube your not measuring air volume and air temp. Is filter and passages clear for flow Before and after filter, I say before as duct tubes can acquire mice nests and leaves etc. if a moron left the duct off my car after repair I,d say this is not a mechanic , very few are VERY FEW! Get another opinion, what was the first reason for repair shop ?.

Thanks Tom, definitely plan on going to a different car shop in the future. In the process of a move so will have to locate a new one once that is all finalized and can actually get my car running again!!! 7jimm7, as far as I could tell car was running great prior to taking it to the shop for original repairs, one thing I may also need to point out is that this car has roughly 107k miles on it now. I had sway bar replaced and some bushings for original repairs, they also checked on the ABS wire harness to see if it was connected properly since the indicator light popped up as well. They "claim" they had no reason to go under the hood for any of these. Sway bar and bushings I could understand, ABS wire harness I would assume would have to be checked either under hood or behind dash. Again, not sure since this is not my cup of tea.. haha... I stay on top of all oil/lube changes and flushings of fluids on a average suggested basis. Hope this helps. Thanks again for input so far!!!

ABS still exists, sent to new location for a second look at the issues. Seems I will be looking into replacing the upper plenum and the catlytic converter after all. Good thing this second shop ran me a couple hundred bucks cheaper. Thanks for the input from both of you!!