Methos was in Grantville when the ring of fire happened, either with or without the others (this could be done with almost any immortal, but if I did it I'd do it with Methos; Duncan would be less interesting because in 1632 he was still a baby Immortal...okay, that might be interesting, too). And he knows that younger!Methos is going to come to Grantville, as well as probably a shitload of other immortals, because it's interesting and completely new. But what's he going to do, leave the only real civilization that exists?