Amemet has 2 PHs, but only 1 will ever be up at a time. One of them is behind the rock, and one isn't.
If you arrive there and all the lizards are up, but there's only 2 behind the rock, then the PH is out in the open area (it'll wander around the entire open area where lizards are, and actually
can wander behind the rock, although this is rare).
If you arrive there and there are 3 lizards behind the rock, one of the 3 is the placeholder. It's random which will spawn next round or whether it'll be Amemet, and he can spawn as quick as just over an hour to as long as 6-7 hours or more if you're unlucky.
When he does spawn, he can spawn anywhere on Guivre's traditional path, and he will start walking. He can change directions at any time, and the direction he starts walking after spawn is random also. He's a pain in the ass to camp with any competition but if you're down there by yourself it's quite easy if you have widescan (to track PH) or if you're into DAT editing. Just time 16min from the death of the PH, and if neither of the 2 PH lizards spawn, you'll know Amemet has, and then you can scout around for him.
He's still very soloable on NIN, MNK/NIN, THF/NIN, RDM/NIN, WHM/NIN, pretty much anything that can enfeeble him or evade him decently. Just have to remember he can petrify so turning often is pro if your evasion can't handle it (NIN and THF don't have to turn, nor does RDM due to shorter petrify length).
Good luck.
