I didn't want to speak for the talents themselves, but please just keep in mind that it's a set of norms that is very different from the rest of twitch or YouTube, because protecting their privacy and personal information (including appearance!) is very important

I see your logic, but in the vtuber space a lot of effort goes into separating the public and personal lives of the streamers. There are exceptions to the rule but I think for the most part vtubers might actually prefer meeting online. It takes a lot of trust to meet in person.

Ok but why is Dan asking to presumably meet in person

It's not the 20th century anymore, you don't need to track someone down in person for a comment

If they wanted people to know they would have announced it via Twitter, YouTube, or any other social media. I have too much respect for Dan to think he's too lazy to check. Therefore he must be asking for information that isn't readily available to the public.

They're public figures with twitch and YouTube channels, why would they be interested in publicly commenting more than they have?

I'm not sure why you're asking, but please respect their personal boundaries. If a vtuber hasn't publicly announced they will be at an event it's pretty creepy to try and find out anyway.