Expand Cardan shaft ???

Hello.

I'm trying to reduce the cardan wave on the A8. After the exhaust and all the heat plates are gone, the shaft on the gearbox can be easily scraped off and removed, the middle bearing is no problem - AAABER: after I have solved all 6 screws, the flange on the rear axle drive does not move a millimeter, meaning that it sits BOMBENFEST on the drive on the rear axle. Attempts with rubber hammers and light blows have remained unsuccessful until now.

The Audi dealer said I should go to work with a Meisel...

Is this possible that the flange is so firmly glued over the years that it does not go off. There is also a seal in between ...

I'm desperate, do you have a tip?

Greeting from the mountains

timmie