Ok guys, a conclusion. I found I was chasing 2 issues. Issue 1, yes the mosfet is bad. I removed it and tested it. It gave me no love. Like someone said b4, these usually fail hot no open. Kinda strange but oh well. Issue 2, the back up heater cart I used was also bad. A while back I had one stop working and instead of throwing it away I kept it to figure out why it wasn't working.
Thanks for the help. Truly appreciate it!