This is hilarious. It's always funny to see someone eat their words. XD
Back to the point, if a user scripts a custom boss then will it be used?
How advanced does the boss script need to be? Just value edits and weaponsets like Ephialtes and Samus, or something new and custom like Mocheeze and Rotondo?
Doesn't take much effort or skill to make a playertype and pick a few weapons, though if someone designed a boss weapon and submitted it privately to us I suppose they'd get some kind of credit for that. Pecon usually pays people for content in donor status, but that's his decision. Ephi doesn't have any special scripting to him, just a fast player and a shockwave. Samus is mostly defined by the power beam, but the scripting isn't that major. Rotondo was credited for the zombie model taken from his gamemode by name.
Of course, all boss designs are subject to our review and modifications, and just designing something for a boss, even if it's good, doesn't mean it will be accepted. It would be better to clear that up with us first to be sure.