John, I did. I can order a custom cord from them, but nothing off the shelf.
I did find this.

It's described as parallel and bidirectional. I get the bidirectional part, but I can't decide if parallel means that that all females connect to the male, but not to each other, which would defeat the purpose for me. If the females feed to each other, I can connect the male from the flash to one and a male PC to female mono to another, then plug the receiver to that.
How does a parallel connection work and is there a better solution?