Hello justinmg.
Had the same problem a few weeks ago, repairing a friends RV9A. His bolt was fitted the correct way i.e. bolt head down. Problem was, the bolt would only turn about 1/4 turn in situ. Didn't want to move other than that. Engine out (only about 1 hour) gave the best access. The bolt was unreal. It was a pukka AN bolt, correct size. Problem was, it was Z shaped, hence the jam. Going by what you are saying, it might be a bit of a common problem. Perhaps the amplified side loads the nosewheel transmits up to the mount bolt are too much for the rather small bolt to accept in sheer.
We got this one out with hammer and copper drift. But, as I said earlier, it was fitted the correct way. You may have to pull the engine, cut the head off the bolt, and drift it through.
Good luck and please post your end result, perhaps with a picture.
camlobe