The PSU has no ability to communicate with the miner. This hypothesis is probably not true.
I do understand how frustrating it can be to have an ant down, and I too have made many incorrect conclusions when debugging rigs. The best way to figure it out is to swap the questionable ant into a working setup if you have another ant from a previous batch. If the known good ant can't run on setup #2 and questionable ant runs fine on setup #1, then setup #2 is bad and you must change things one at a time in setup #2 until you pinpoint the issue.
It sucks, but that's debugging. Spend an hour working methodically, and you'll be better served than 4 hours flailing angrily - trust me, I've done both. Many times.