Did your lamp just die out of nowhere or was it on its way out for a while? A buddy of mine rigged a PID on his setup after a similar meltdown and he says it was the best $80 he ever spent. He still cuts by hand, just doesn't babysit the heat anymore.

My third batch of macarons was also hollow and it turned out my oven was running 25 degrees too hot, not my folding. I bought a cheap oven thermometer after that and it fixed like 80 percent of the problem. The folding thing matters but people online act like it's the only reason they fail and it drives me nuts. Your aunt probably means well but she wasn't standing in your kitchen watching your batter. Next time try baking one test cookie first before you do the whole tray, it saves you a lot of heartbreak.