Don't think I fully agree with Paulwho. The bolt has a countersunk tapered head that offers a very large bearing area and it's only function is to keep the splines intimate. MB has also seen fit to add a threadlocker compound to the bolt. In my opinion the threadlocker compound is typical MB overdesign paranoia.

Older Benz used a conventional hex head bolt and in that case a threadlocker can be justified. I think the only reason to replace the bolt is if the Allen recess is buggered. I have had my wheel off a number of times and never replaced the bolt. The notion of the steering wheel coming off while underway is absurd.

I believe you can safely re-use the bolt and despite what the instructions say Do Not Use impact to seat it or you will be right back where you are now next time you have to remove your steering wheel. One good grunt pull on a breaker bar is enough.