I don't know if I responded to your question in another post ?
My 99 Freightliner chassis , the 2 flashers are within inches of each other and less than a foot of wiring separates them from the fuse/relay centers.
If you can track the signal flasher by it's sound the hazard should be close by.
The 2 flashers are hanging between the fuse boxes in this picture.
Because the flasher is on the outside of the firewall , the coach uses a beeper under the dash to warn the driver the signals are on , if your coach uses a similar set up you may have to disconnect the beeper to track the click of the flasher.