I've never seen any credible reference to them being TTY bolts except in this forum.
However, if you insist on over-torquing them, you will certainly need to replace them, and possibly prior to any planned maintenance.
In general, a TTY bolt has a torque value and then an additional degree turn after the torque value is reached. The torque value will seat the bolt, and then the additional turn provides the stretch. Once stretched, a TTY bolt cannot be reused.
Axle nuts can be reused, but VW will disavow you if you do. It is more a corporate liability thing than a nut that might come loose thing. I've never heard of anyone's axle nuts coming loose when properly torqued. Some people insist on using locktite (red) on them, however. But they're not expensive, so if you want to replace them every time, the local parts guys will be very happy to keep selling them to you.