Over heating when pulling

What is your question?

I recently had a different air filter by S&B installed and now my truck overheats when pulling. S&B says it isn’t their filter, that the installer may have “damaged” something. Digital readout of temp come on above gauge for transmission and engine temps. Engine up to 221 and tranny up to 224. When it kicks on, I back it down and don’t let it get higher. But I can turn on the heater on high and the temps come down as well. Ford cannot reconstruct the temps since they cannot pull a trailer with it. They said the fan clutch was bad, swapped it but still have the same issue. I’m at a loss and wondering if a wire could have been damaged or what. I never hear the fan completely engage even when hot. Thinking a sensor maybe? Or bad luck and got another bad fan clutch?

What makes this problem better or worse?

Pulling. Ambient temps at 80 and overheating on flat land down I-10.

How long has your 2018 Ford F-350 Super Duty had this problem?

Few months, multiple Ford dealers with no solutions.