I would challenge the idea that the PCM is failed at this point. It very well could be but I would want to see the proof after being told it was a transmission and that was not correct.
The idea of what is happening is the vehicle appears to skipping shifts most likely due to inputs to the PCM. This is most likely the throttle position sensor because this is a major input that is needed to determine proper shift points and correct gear.
So if the throttle position is not operating properly then the PCM will not correct it.
Again, if there is a reason that the PCM is failed, they should be able to show that. If not, then I would seek a second opinion if you are not going to look into this yourself.
Please come back and update us on what happened with this and we can go from there. Thanks
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Thursday, March 26th, 2020 AT 4:34 PM