Swarm "mismatch" preventing a network build

So I set up Swarm Agent on four computers in the office (one as coordinator). It lists all four and says they are assigned to me (coordinator), but Swarm isn’t handing off any light building to these other machines. You can see that one or two are “busy”, but what concerns me is that a network ping says that all the IP addresses failed to verify. These are on the same local network, so what’s going on?