I have no opposition to TVA sponsoring the convention and would be willing to spare a few quid if need be, but I do think it's worth fully emphasising to them that we are a controversial community in the vtuber space and that we discuss both the positive and negative elements of vtubing before shaking hands on a deal. I could see a potential outcome I'd prefer we avoid where they just quickly skim the site and accept the sponsorship, only to be ill-equipped to handle the several hundred rainbow-flag bios, unicorns, and /vt/ shitstirrers accusing them of promoting the neo-nazi doxxmaxxing forum, especially as they might lose some other sponsors and/or talent appearances if it blows up too much.
If they know what they're getting into and accept the sponsorship anyway it would be a genuinely positive sign that they're willing to filter out fair-weather fans who'd be a liability if they don't get their way, but if shit goes south and it falls apart I could see this being spun as us sabotaging it, because that's how the loudest voices in the community tend to work.