Did you figure it out yet?
I have an 11 2.4 awd that acted similar with 114k. I had massive issues in trans had a total rebuild but it was also slipping as well as reving weird. Fixed trans issue with 3/5/r slips and bang into gear, and slipping. Then after that I had the high RPM like sometimes it would get up into very high RPM before shifting but not slipping and no code. Again this continued after transmission was rebuilt (soup to nuts rebuild even torque converter replaced). Trans shop had no idea exactly the cause but guessed it was part of the whole electric system and not the actual trans and gave me some tips and I think you might have already tried what I did from the post. They weren't pushing me off, they actually said they would take it apart again and check it out but to check about other things first as they drove it too and it wasn't slipping like it was and was shifting just wasn't behaving as expected.
So finally I replaced with new (after cleaning didn't not fix issue) the throttle body complete. Of course it instantly threw a code as you expect with out a complete reset. I did contact a dealer mechanic who said do it anyway make it throw a code, and see how it drive if it drives differently with the code you have a result. It did drive differently but not correctly but a different result. I asked him again about it he said to go through a reset procedure after clearing code and doing the battery off for 30 mins. Although he said he wasn't sure which one of the at home resets would work. He had me do the off gass pedal hold for 30sec turn key on with pedal down, for 30 release for 30, then off for 30 then on press pedal down for 30 then off with pedal held and release. Then said turn everything off inside car with key on engine off then then with all doors shut turn key off then back on to start no accessories on and let it idle till warm at least 5 mins or more (I waited for about 10. Then off then start and idle 3 mins, off for 1 min then start and idle for 3 mins. Then drive. And he warned me it will relearn as I drive give it a few drive cycles before making a judgment on fixed or not. It was fixed and learned to shift normally again.
After reporting back to him he said yes it was probably the throttle body electronics specifically the throttle position sensor. In it, or the control motor, most likely position sensor. He claimed it effects shifting, based on where you put the throttle, which makes sense and said that unless it goes out completely for enough time it would code. He also so if there is any more issues I should change the pedal too for the other side of the sensor. Also recommended I check wiring on both ends for cracks and brakes or connector issues.
Anyways hope this helps.
The take away for me was I had multiple issues, but the car was a bit of a gamble I bought it damaged. It was bought for metal weight paid 300 bucks as the previous owner was told me had a trans issue, as they did, it was slipping and not good going into gear in 3/5/R, and engine issues (I had did the timing myself complete with water pump and all too). So with the purchase price, timing, brakes, tires, cat pipe, a few other bits, transmission rebuild, and throttle body, I had just over 3k and many hours of my time, in a 11 awd with 114k miles that was after 1k in shaking it down again, inspected in the annoying state of MD and working well. Side note not sure when but someone had previously did work in that motor found out when doing the timing, which was just starting to rattle chain with no codes. You could tell I had previously had work. Dealer said I had a past engine warranty work but they didn't do it and it didn't say neither it was an oil eater that got fixed or not. But it doesn't seem to be eating oil so far. If I was the original owner of this I would have been pissed if it got this bad in 113 to 114k after seeing how many others didn't make it this far. But in reality it's a cheap car for this price. Yes I am rambling.
