Flex coupler! Thank you!
So it is now off the car and the stub axle is still stuck?
Sorry, I thought this was where your problem lay as on my 600 once I got the coupler off the shaft just slid out.
Its obviously bet into a bearing, with the coupler off can you pull the rear seal off and again soak everything with WD40 or similar, leave it to penetrate and then hit the exterior of the bearing case and see if frees? See if it will release with shock?
Have you a spare steel rim that you can put back on and use this as leverage for pulling from the side and hitting all round from the back?