Since the drives don't spin up, the problem is most likely PCB related. Either the PCBs have failed, or there may be 3.3V present on SATA power pin #3.
Power Disable Feature (SATA 3.2+ / 3.3):
https://www.hddoracle.com/viewtopic.php?p=13846#p13846If you narrow it down to a PCB fault, upload detailed photos of your PCB(s) and one of us will show you where to test. Sometimes there is an easy, no cost, DIY fix.
See this thread:
https://forums.tomshardware.com/threads/dead-pcb.3781397/#post-22827395Archived photo clips:
https://web.archive.org/web/20230522150711/http://www.users.on.net/~fzabkar/HDD/0A90601/