I have a dodge transmission known for its petulance when any other fluid but ATF+3 and now, ATF+4 is used.
After a bunch of torque converter clutch chatter an a run around from Aamco regarding their rebuild of it while still under warranty, back in '03 or so, I had a dodge dealer exchange all the fluid~12 quarts with ATF+3, and no more shuddering in lockup.
NOt too long after this exchange with teh proper fluid, I had an electrical issue with overdrive and brought it back to Aamco. they wound up pan dropping and using 4 to 4.5 quarts of their bulk universal ATF.
I nearly blew a gasket and started foaming at the mouth when they told me it is just as good with their special additive.
But the shuddering did not return with the diltued atf+3, but I did drive X country, and dropped the pan, added a drain plug and did some more 4 quart exchanges twice over the next 6 months.
The elextric issue I later figured out was the vehicle speed sensor, on the speedo cable. Several years later, I found all they did was clean the contacts.
facepalm for not being wiser to the importance of electrical contact conditions much earlier in my life.
Not sure how much capacity your Tx has, but 2 quarts of dexron in 8 total quarts of ATF+4, while not ideal, should not be instant death. My tx dipstick actually says dexron on it, and this was later defined to mean that topping up with Dexron was OK, which I find to be bull pucks, but so be it..
A drain pan in the plug makes dropping and replacing 4 quarts on mine, easy.
And now I have a recently installed warm and fuzzy remote mount filter which should make future pan drops for the new filter in there, not necessary for quite some time.

Now for some extra Neodymium Magnets to line the filter's exterior with.