Stuck - what to do now?

[Lucky Thirteen]

I'm kinda stuck in the desert.
I talked to Jean, he joined my party and I went about some business in the Tribes and the Oasis. At some point, Jean left my party, saying he'll go prepare the boat and that he'll be waiting for us.

Now, he's nowhere to be found
He's not in his house or anywhere nearby, and when I try to go where his ship is supposed to be, the Fisherman says: "Jean doesn't like it when someone goes near his boat." and it won't let me go there.

I'm not strong enough to beat the Djinn yet, so I didn't go down the hole and didn't try to fight her.

Any ideas? What do I do?

[.]

Do you have a save file from before Emery joined the party?

[Lucky Thirteen]

No, I don't
Didn't think I'd need to keep that one.

[.]

Jean isn't supposed to leave the party unless you have Markus; regardless of what order you choose to play out events. We'll update that today, but the change won't add him back into the party if you've already saved. If you can't beat then Djinn, and get Markus, with the three party members, which will bring Jean to the boat in Billies Tribe, then please email our [e-mail] and I'll get Jean back into the party for your game.

[Lucky Thirteen]

Great, thank you!

Will try to beat the Djinn again later and if I can't beat him, I'll email you.
Thanks again