UPDATE: Took it apart, heat definitely worked! Appreciate all the feedback as well.
So after being able to take a look at it, there will have to be three things done to the air shaft after it is taken apart.
1. I will have to first take off 5mm from the end of the shaft
2. I then will have to cut threads a few millimeters further, going to check if the school has the tap that is close enough to the original so I can chase the current threads then tap new ones.
3. I will then have to drill a 21/64 recess in the inside to allow room for the seal and metal bit at the beginning of the threads, all is pictured below.
Once I can confirm that the school has what I need, I will order a 170mm airshaft and get started. If there is any flaws you guys see, lemme know!