The collector finally spawned again after wandering back and forth for awhile. Not sure how I made it glitch but I was able to defeat it. I was stuck on the Devouring Maiden where sometimes their health would be almost nothing after fighting from inside them once but other times I would have to do that 3 or 4 times before it was damaged significantly. Then it started getting stuck and flashing against the right wall and I was able to get the last hits in during the glitch and progress. Oops.