The big concern should be if the combination is hooked up........ can you in any way lift the the caravan hitch of the towball without touching the handle?
If you can't I would say that your combination is safe for towing. Why I am saying this is that for the caravan hitch to be able to come of the towball something must actually lift that handle against the spring tention inside. This is not likely. The catch is something addisional and all I would do is clean it. Remove the grease and oil specially there where the catch hooks if need be just sharpen the edges with a file and you are good to go.
Something realy drastically must happen for the handle to be lifted by itself and by that time your rig is in much other trouble than worrying if it will unhook.