The context of her having made a callout post beforehand and the incident taking place in the most anti-corpo climate this industry has ever seen pretty much forced his hand into being nice to her on the way out.
I don't think Riro's dismissal is an exact 1:1 comparison since he had to admit that one of his own staff was acting inappropriately and get the official version of events out before the rumour mill did its thing and Chinese Whisper'd the narrative into Idol covering up a grooming incident, but the termination notice overindulged in shaming her beyond that. Framing it as "Riro was involved in an inappropriate relationship with a member of Idol staff, who has also been terminated, among other breaches of contract" instead of a bullet-point list telling everyone she's made for the streets would have been more dignified, while still telling people what they need to know.
I don't doubt that Aviel was absolutely livid about the way Pochi's falling out and departure played out, but he's a businessman above anything else, and recognises there's no good optics in tearing her apart publicly right now. The Legal Mindset stuff tells me Idol's current plan is to acknowledge the "corpo bad" sentiment is at an all-time high because of the Niji implosion, and present themselves as One of the Good Ones.
They have an unusual gimmick in that they've pre-emptively announced their graduation date like a kind of VTuber Unus Annus, but unlike UA which featured well-established personalities who promoted it themselves, this person seems to have popped up out of nowhere with suspiciously competent marketing efforts and a quickly-established network. It's very curious, to say the least.
