Okay. It’s the idea that your blu-ray players don’t have ISO support that’s confusing me. They don’t need to play an ISO, they just need to play a disc. An ISO is an image of a disc, but when you burn it as an ISO, it just puts the whole layout of the original disc onto the new one. You should not have an .ISO file on the disc.
When you put the disc in your computer and browse the files, do you see a BDMV file on the root of the disc?