Not your typical 4wd engagement issue - Any Thoughts

Hello, I have a 2010 Tundra DC 4wd just acquired stepping back from my 2016 crew.

So when I got this the dash was a Christmas tree and the rear actuator motor was frozen. Did the research and installed a new front actuator and swapped out all the rear actuator components from a new one, minus the rods.

Current situation - No codes or lights under normal operation in 2WD. It use to have some PDTC's that went away after some driving with my new parts installed.

Still have no 4WD. The upper actuator will cycle and lock the driveshaft to front, but no activation of front actuator. The 4Hi light will blink slow, then after 10seconds or so, reverts back to home 4Hi blinking fast and front shaft unlocked. Will be normal back in 2WD. As you could imagine 4lo doesn't happen until the ECU has confirmed the 4hi steady operation.

Some might say this is just timing(I have tried so many techniques found here and abroad), but I am not convinced of that unless there is some magic setting with one eye closed. I have done the shafts all the way in, set the contacts various ways with the same results. Even with the motor off to allow random fitment and let the system find home, the same results. There is a nice video (although not in English) of the exact install method without splitting the case, however, he set the shaft out and actuator motor at a more neutral setting. My results have been the same no matter how many variations I have tried. Mechanically, you can shift through the operations like normal, so no apparent mechanical driveline issues. I have heard of internal detent failures that may cause this, but trying to avoid ripping the case out.

I am wondering if the 4wd ECU module went faulty based on the previous owners driving with Christmas lights for so long. The main PDTC was P0818, but is since gone now. Toyota rep said the module rarely if ever go bad... take that with a grain of salt.

Any thoughts on how to align or just pinout ecu and rule that out. Every shop I have had a conversation with wants to split the case because they don't want to mess with the actuators or have no real knowledge dealing with the 4wd system diagnosis itself.

This vehicle didn't have alot of 4wd use and has a fairly clean undercarriage.

Appreciate any info to get it going properly. Thanks