Sorry I can't answer your question (ie where to get a massage in a more "gay environment" without escort services) but I would recommend
www.healthlandspa.com. Generally more upmarket and more expensive than your standard BKK massage, but cheaper than a hotel service.
Health Land Spa seems to have four locations in BKK. Is there a particular location that any of you would recommend? The maps don't make much sense to me, but I'll be at the Conrad, so something close or reachable by Skytrain would be good.
As for the Babylon, I've had massages there a few times. It is generally legit and very cheap, but the quality of massage isn't all that great.