Ah! I should have noticed this sooner.
Executor and OrderMatch are both server-side applications, so they won't talk to each other, as they are both defined as Acceptors. When you run OrderMatch, it's an Acceptor, so it's looking for an Acceptor entry in your config (which configures an Initiator).
The TradeClient example app is an Initiator. Use that instead with either Executor or OrderMatch.