Kodiak ZTR 50 commercial stalls when.....

I have a 2006 Dixon Kodiak 50ztr. When I bring the controls in it stalls, when I engage the blades it stalls. If I play with the handles and position them just right I can get the mower to move, but when engaging the blades it'll still stall. I was thinking maybe the seat switch? Anyone have other thoughts? I can't take it anywhere because I don't have a trailer. TIA

I think you think right.
First step is obtaining the wiring diagram
Then make some patch cords ( nerd name for light jumpers ) with 1/4" male spades on each end
Pull the plug on the seat switch and using your patch cords jump the socket to make the connections that would be made with you in the seat.
Being that the engine stalls in both cases, levers in drive position & when PTO is turned on that screams out seat switch as it is common to both.
You mower has a relay connected to the seat switch so if jumping the switch plug makes no difference try substituting a good relay or jumping the relay socket.
IF jumping to socket works & the relay is also good you have a short or broken wire between the relay & the seat switch socket.