Sounds like the button on the shifter.
When you try and shift you usually cant unless you push the button in on the shifter. That needs to pop out and release the mechanical part that pushes on an electrical switch.
When i put a different shift handle on mine i put the shifter on so it kept the button pushed in all the time. I had this same issues it wouldnt release the key.
Once i took the shifter off the button poped up and it then released the key.
I figured out what switch it was pushing and i then cut the wire so it was always "un switched" it works fine now.
Try pushing in on the button and let it pop out, maybe its gummed up or something so its partly stuck in.
I think you might be able to press the switch if you poke a key or screw driver into this slot under this little plate cover thing.
If i remember right this is the switch that releases the key with its out. Pushing a key into the slot under the plate might work it enough to switch it and relaese the key.
The black and yellow lead from the switch is the one i cut so i could use my own shifter and still shift and remove the key.
been running the walmart green skull thing latley lol hope this helps some