Personally, for all it's worth, I'm on Hidden Masta's side concerning Kougami and his motivations. So far Kougami hasn't displayed any clearly evil intentions or performed any clearly evil actions; yes, he apparently allowed his soldiers to die in a hopeless fight against the Greeed, but I think that particular battle was so brief that I doubt Kougami would have time to order them to retreat anyway, once the dying started.
Kougami's intentions and motivations for gathering Cell Medals might well be personal and "evil", or they might be completely altruistic and for the betterment of mankind as a whole. We don't know, and even though we can make guesses, we won't know until it's revealed in the show itself.
Sure, going by how supporting organizations USUALLY turn out in Heisei Rider shows the Kougami Foundation will indeed turn out to be evil. But we don't know what Kobayashi has in mind, and Gotou is already going against the usual "asshole 2nd Rider" trope, so she may well prove us wrong :thumbs: