Just to sum up:
- on mac, creating virtual ports directly in open stage control is better and simpler, no need to use IAC [done]
- the server's debug option can help seeing what's sent by open stage control [done]
- MIDI Monitor can be used to confirm the message are sent and can be received [done]
- now you have to troubleshoot the receiving end (wrong midi channel ? conflict between generic remotes ? hard to guess here since I don't use these softwares). Maybe try using a different control surface software if you can, or even a hardware controller, it could help pinpointing the issue.
Sidenote: you don't need to write anything in the server's send option, especially not something like 127.0.0.1:8080, since that would only route osc messages from open stage control to itself (if its port is 8080), besides you seem to be interested in sending midi only (not osc).
Edit: I hope this doesn't come out too harsh, just trying to prevent the topic from going in all directions at the same time.