This is hard to explain, as the pictures I took don't have enough contrast to help out - but I just installed the disconnector that came with my recently purchased 922R kit. While its width is thinner at the top, it's actually thicker at the bottom where the pin goes through. Hopefully, this will prevent the break experienced in the OP.
I removed the original by pushing the pin from left to right, towards the trigger spring but only enough to first remove the collar and then a bit more to remove the disconnector. I attempted to install the 922R disconnector in the reverse order, putting in in first, then the collar. However, the collar doesn't fit going in this way due to the thicker bottom section of the 922R disconnector. I had to put the collar in place first, then place the new disconnector on top and push it down.
The reason for this is that on the original, the slot that the collar fits into on the disconnector is machined like a dado (sorry for the woodworking analogy) running from bottom to top. On the new one, the slot for the collar is machined more like half of a mortise (upside down "U") from the bottom and goes only high enough to allow the collar to fit. This allows the whole bottom section of the disconnector to remain thicker and stronger (?) and is why the collar needs to go in first.
For what it's worth, might be interesting to know if the other side of the broken disconnector in the picture above has a slot going all the way or not.
Sorry for the ramble. Probably should have just measured them for comparison! Too late now and I hope I never have to get in there again.