Looking to book a flight from DPS to USA via TYO. I see dynamic availability on the US portion (110k each) and partner availability on Garuda, but wondering if there is a way to book it as one ticket, and if I would get any mileage savings as a result.

I surprisingly didn't see much when searching for this here or Reddit, does anyone know what the general process is for booking awards with JAL + 1 partner (oneworld or non-oneworld) in terms of number of tickets and how they determine pricing? The website didn't offer much that I could find, although I could have missed it when looking through the various pages.