found this out by "accident" and it turned out to be a good thing....
used an extended "stinger" (???) with a really long trailer that helped a great deal with the trailer tracking a lot closer to the TV's wheels than before (didn't have to take corners so wide)
an extender increases the distance between the rear wheels of the TV and the ball....as the TV starts to turn to the right the ball is actually going left....an extender exagerates that
back to original problem though.....I think you could take your problem to a good metal fab shop and they could make a semi-permanent extension for your trailer that would increase the distance...but could be removed is you gave up the bikes....imagine something that would fit into your coupler and be stabilized by two welded arms bolted to your frame....with a coupler ahead of all that.....trailered boats with keels use tounge extenders all the time...but not for highway towing obviously....that's just where the idea came from...
either way, now you're looking at a possible other problem...are your chains and
electrical cord long enough ???? good luck