Skeleton: support rods on wrong thread

We are trying to fix our skeleton which is unstable and keeps toppling over. The support rod for the skeleton itself is connecting to the support rod on the stand by a nut, and both rods have somehow got on the wrong thread. I'm trying to separate them but they are totally jammed.
Normally I'd take it down to DT to see if they can do anything, but we don't have a DT technician around at the moment. Any suggestions?
First I must declare my commercial interest -Down here in Australia I run a small retirement business repairing equipment for school science depts.
As such I repair many skeletons each year - maybe I can help with ideas?
Can you post some photos please?

I'm guessing it should be like this...
Looks like yours has been bent over, which has probably stretched the thread. Not an easy job to recover.

Try first gently bending it back straight so as to get the thread as close to straight as possible.
Then you will need to clamp the skeleton end in a strong vise, apply some oil to the thread and then turn the stand a little back and forth at a time hoping to reshape the thread and wind the stand off, slowly bit by bit. Do it very slowly and let it cool a little bit every so often to prevent it work hardening.

you can get it off.... then you need to find someone with the correct size tap and die to run over the threads to get them right again.
If you cant find a tap and die, you can find a matching bolt and nut from the local hardware and with lubricant, gently wind them onto / into the threaded parts, once again in a back and forth motion to reshape the threads.