Try to see if the lever isn’t jammed, see if it moves when in gear
, you don’t have to start the engine
, if it moves in gear, then it’s the lever and not the cable.
I have had mine jam once and wouldn’t move, and it hasn’t since, felt like it was half way disconnected, wiggling the lever and pushing the button back in and ensuring it was fully out the next time seemed to clear it.
I’d wiggle the lever and push the button in and pull it out once or twice before I disconnected the cable, but if the lever seems fine, I’d go to the cable next, especially since it’s sat up, but once cable is loose try the lever on the injection pump
I would not start the engine
for any of this myself.