tried the test that mystic said with a test light. points 2-3 had light on when open and off when closed. points 1-4 light stayed on when open and closed.
Good! Making progress. Your test with the ground wire, btw, was good thinking. If you hadn't thought of it yourself I'd have suggested it next. Remember that one for future use.
Light stays on = points are never making electrical contact. (btw, light always off = point is grounded)
Even if the point faces are crooked, they should be making SOME contact. Try pushing the point closed with your finger, does the light go out?
First thing I'd do is re-set the gap on that point, it's possible the gap is too large and therefore the point is never closing.
Assuming that's good, are these points new or used? New points are fairly inexpensive. If you replace them, get new condensors too. Sometimes you can find them all in one box in a "tune up kit". Research points here on the site, quality varies between manufacturer.
Meanwhile, I'd dress the points faces if they're not square. What sort of file are you using? Clean the points with contact cleaner or brake cleaner afterwards, the oils from your skin are enough to throw off the resistance. To see if they're clean, set the points to fully closed, open it with your finger, and insert an un-laminated business card or other similarly thick paper (not too thick). Let the points close and then draw the card out. If the point faces leave streaks on the paper, they were dirty. This process also cleans them though, so repeat until you have no more streaks.
Your mission is to have point continuity when closed and none when open. Let us know how it goes.
mystic_1