Nidoking is a great baton pass recipient, yes.
Since I don't actually play ubers, I have a question. Is Sacred Fire the only thing keeping Ho-oh in ubers (let's ignore regeneration for now since it's unreleased)? When thinking about it, he doesn't hit any harder than Garchomp does. Sacred Fire is as strong as Garchomp's earthquake. Brave Bird is as strong as Garchomp's outrage. Garchomp is faster than Ho-oh, has a better offensive typing, and has the means to actually boost his typing. Garchomp's dual STAB actually help him get past what would normally resist him, while Ho-oh's dual STAB is somewhat redundant. Fire and flying are both SE on bug and grass, while both are resisted by rock. While Ferrothorn/Nattorei would NEVER switch into Ho-oh, he loses around 48-56% from adamant choice band brave bird. Rotom-W 3HKO'd by the same brave bird, which is Ho-oh's strongest attack. A rotom-W with no offensive investment can land a solid 2HKO on max hp Ho-oh with hydro pump. Theorymonning here, but Choice Band Ho-oh would have the same switching issues as Choice Specs Latios, with pokes taking advantage of whatever move he's locked into, switching in and setting up. Ho-oh's base 90 speed would not be too kind to him either, nor would the SS residual damage and Stealth rock damage he would have to dodge around. Base 90 defense does not matter either when his typing is far from defensively admirable.
Then again, unlike Garchomp, Ho-oh has access to two forms of reliable recovery (like Latios) and a way to boost his speed. While his typing may not work for it, he's also much bulkier than Garchomp on the special side and can could possibly get away with actually using a calm mind set if he were in standard. I also don't play ubers so I may be missing something obvious here. But still, what is it that pushes him over the edge, while the likes of Garchomp and Latios are A-ok?