Obviously an AI post (dozens of these with a very similar syntax over the last few days), but just for shts and giggles:
1. Just leave them. No advance talk/note/message/call. Cut all financial support immediately.
2. Have some fun in Pattaya for a month and have coitus with 100 LBFMs. Try to stay off the booze. Go to the gym every day. Don't fall in love with the next hooker.
3. Re-evaluate after a month if you want to stay here in Thailand or go back to your country (not sure what the financial situation is).
4. Forget the kid. Kids do just fine here (especially in the sticks) without their daddies. This isn't as bad as the 'Murican single black ghetto on foodstamps mom situation.
Offer to take the kid with you either to your new home here in LoS or your home country, with full legal custody, if the wife agrees to it. Incentivize the agreement with a one-time payoff, all contractually via lawyer and approved by the courts. All dependent on a positive DNA test, obviously. If she really loves her kid, she'll refuse and then you can at least have some small relief that the kid will grow up somewhat ok, but then you must also, in fairness to the situation, cut yourself off until she reaches late-teens/adulthood and gets to her make her own choices.
Not a lot of 'winning' scenarios here, but it's not the end of the world.
Again, one thing for certain - stop paying for all these village idiots' habits and/or bad decisions.
It won't do your daughter any good, now or in 15 years, to have a broke ass pops.
Best of luck and success.
PS. Get the kid her 2nd passport regardless of how things turn out, if you haven't done so.