The Sailfin should work, from the standpoint of parameters. Depending upon the cichlids, he may get a beating, but that's another issue from the question asked.
The Dojo, definitely not. This species needs softer water, and much lower temperatures (it is not a "tropical" fish as we generally understand the term). You are correct on intending three, as this is (like most "loaches") a highly social fish, but not with African rift lake cichlids.
Corys will not do at all well with rift lake fish. First, the hardness of the water will affect the physiology of most species (a couple will handle this). Second, most of them are not suited to this environment (fish and habitat).
As for other loaches, I am not aware of any rift-lake species but this is not my area and if there are, they might work depending. But none of the SE Asian loaches.
Byron.