Very interesting discussion.
Seems like ServiceNodes could be an impartial third party to an escrow. You could do a fall back to an arbitration service if sellers and buyers do not agree on something.
Either way, buyers and sellers pay ServiceNodes for the service. Add a little obfuscation for the IP addresses and it could be a relatively easy win.
Maybe add a shapeshift type service to allow escrow between crypto currencies, crypto and fiat and even just fiat to fiat transactions.
If they could ramp up over 2-3 years to do $10m per month, at an average of 0.25% in fees, the network could earn $300,000 month or $3m-$4m/year. The network is currently worth $30k!
1,400 ServiceNodes in the network would each earn $200 month. If you had 20 servicenodes, that could be your full time job

The value of the global escrow service must run into $billions. We are only talking about a rounding error in that market and you still get a highly profitable use case.