Hi!!, anyone know if it's possible to create these payment event records via script? Not showing up in the .type enum

You can't create and/or manipulate those as far as I know, they are created via your payment processor, the best you can do is to understand how your payment processor works and build logic that searches, parse those and make decisions based on that.

Payment event will be created by payment plugin script. You need to contact NetSuite to enable payment plugin script