It's just one of those things. Main thing is that you know for future reference now, so can chalk it up to experience. I'm sure we've all had occasions where the penny has only dropped late on in trying to remove something which is stuck. I had a cranked arm on a taper last year, for example, which was an absolute b**ch to remove, and it defeated all of my best, (and worst), efforts. Then, someone happened to mention a simple method to try. Blindingly simple in fact, yet it sorted it in a flash.
It is a ****** if something happens to break, (but saying that, we're less likely to learn well if we don't make mistakes occasionally), but you should be able to make an almost invisible repair on that. It should be almost as strong as was too, between the dowels, screws and braze.
