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Limp mode=bad PCM?

My 05 Acura TSX went into limp mode a few mts ago with a U0107 DTC lost communication with throttle actuator control module. I followed all the steps in the factory service manual for diagnosing the DTC and every test was normal (voltages, continuity, resistance). i replaced the TAC module per instruction in service manual flow chart but still have constant limp mode & trouble code won’t clear.
The car was taken in for a recall about a month before this happened for corrosion on the ECU. I managed to find the actual instructions the Acura service dept went by and they say if corrosion is present on PCM to check for codes and only replace the PCM if there was one particular code (which stands for the PCM not communicating), otherwise remove the PCM, clean it, tape a (cheapo) cover on top & bolt it back in place with the cover (which has a hole for one of the bolts to fit thru).

Aggravated beyond belief one day i decided to pull more trim out of my interior. I was just planning to visually trace more wiring because I had been stuck for months after doing all the diagnostics (even extra stuff that the manual didn’t even mention in the U0107 diagnostic instruction). id had yt? the passenger trim removed already to get to the PCM harness connectors but i pulled out the drivers side trim which exposed the other half of the PCM & couldn’t believe how much corrosion was CAKED all over the drivers side PCM & below it. back when i removed the passenger side trim to get to the PCM connectors id noticed that the cover for the recall was just thrown in the space where the PCM is… not attached at all. but at that time i hadn’t learned that it was supposed to be bolted down with it. After realizing the dealership should have had the cover bolted down it made me wonder if they didn’t because they were unable to remove the bolts. I tried for months to remove the PCM but the bolts were so stuck it took literally hundreds of tries, tons of lubricant and rigging up a longer handle for a wrench in order to get more torque b4 finally getting the bolts out! the amount of corrosion couldn’t have accumulated to that extent in the month between visiting the dealership & when the limp mode started! (it was June & we hadn’t had any rain plus my car stays in the garage).
I’m just looking for some advice about this… All of the throttle related Preformatted textsensors showed normal voltage & resistance readings. Also normal at TAC module, it’s relay, PCM harness, fuses…grounds are good, battery is new & good.
Could corrosion cause a PCM to throw only one false trouble code? am i wrong in thinking Acura is incorrect to act like a corroded PCM would definitely throw that one particular code, I’m thinking it’s P0606?
I’ve had this in drafts for awhile but since then I’ve opened up the ECU & found corrosion all over the PCB inside! One of the IC’s was so badly corroded that one of the lege just decenagraded and at least one other leg is lifted…not attached to the board anymore! I’ve searched the imprinting online but there’s no info anywhere about this chip! I wish I knew how to add pictures on here bc I want to let
you guys see the chip and the corrosion!! the imprint says:
176 432102
the engine is a K24 vtech automatic pcm# 37820-RBB-A55
The pin that’s gone is pin 26…the ic is a square QFP chip 56 pins and right beside the EEPROM immobilizer chip on the board.

Based on the picture you posted, I think you need to go back to the dealer and confront them in a firm but polite manner . . . especially considering the recall was “for corrosion on the ECU.”

Apparently you didn’t have that PCM not communicating" code . . . correct

You had a different code, correct?

At the very least, you should be given an explanation as to why they didn’t mention the corrosion, which is obviously present