After fixing lots of German seats over the years (only two OEM seat builders, irregardless of car make and model), I can share that the problem with power seat drive cables coming unseated is very common.

Trying to glue or matchstick one end will inevitably end in tears.

Either replace the cable assembly (expensive, hard to find, and difficult to R&R), or shorten the cable housing.

To do the latter, simply pull the inner drive cable out (looks and works like a greased speedo cable, and accepts glue and matchsticks about as well), then cut a 2 inch piece out of the plastic cable housing in an easily accessible place. Slip a 4" piece of fuel hose (generally 5/16" or 3/8" works fine) and a couple of hose clamps over the cable housing ends. Reinstall the inner drive cable, make sure it is seated in both ends, then snug the housing ends together under the fuel hose. Lightly clamp in place, and you're done.

This fix is quick, easy, and permanent.