Possibly. Off the top of my head, the collabs I can remember:

1. blessing 2 dusk: I think he still has the blessing 2 at 3* value on his ranking list

2. 7hz dioko: the 7hz timeless was at 3* value on the list, and I don't think he's updated it to include the LETSHUOER S12 yet (pretty common theme going forward)

3. truthear x crinacle zero: he made a video about this one, but it's not on the list. tbh I'm not sure what competes with this, but there's been a massive explosion of budget IEMs recently and none of them are on the list, so I'm really not sure what to compare it to

4. 7hz Salnotes Zero: he made a video about this one too, but it kinda blew up in popularity before he made a video on it, because it was the first post moondrop chu budget IEM that matched its tuning and had a removable cable. it's not on his list either, along with any of its competitors (wan'er, Quarks DSP, cadenza etc) and the only one on his list currently in this realm is the Moondrop Chu with a 3* value rating too.

I don't really know what else he's done, I guess something in the $200 range and something above $1k? But so far it seems like he's been pretty impartial about not letting his collabs influence his ratings, and I hope that kinda sticks with the revised list. It would definitely be suspicious if he rates all the budget IEMs as 2 star for example and just says "worser than the 7hz zero", but I think if he just compares them with each other and excludes the 7hz zero (as an example) then it's pretty legit

A few of his colabs were paid in a single lump sum (couldn't tell you which ones off the top of my head, just remember him mentioning this). Still, you have the idea of prestige, but even then from having watched him enough and listening to a lot of headphones his tastes lines up close enough with mine and my opinions, so eh idk I'm still fine following him for general recommendations