speaker-test -Dsysdefault:PCH -l1 bypasses pipewire and speaks to the soud card directly using ALSA.
If the channels aren’t muted (as we could see in the alsamixer screenshot) and if he still didn’t hear any noise generated with speaker-test -Dsysdefault:PCH -l1 (the output he posted showed that the command ran successfully) it indicates to me that it is a low level issue somewhere between alsa and the hardware.
At this point I’d actually boot into a live iso environment and run the speaker-test command there to eliminate a hardware issue.