There's at least one person from Nissan USA posting here, possibly more. I think Blink has a rep here as well.
IF a user wishes to reveal their affiliation, it should be confirmed by an admin (via an email associated with the company). Then instead of seeing "Forum Supporter" under their username, it would say something like "Nissan USA employee".
I'd suggest having these groups for any EV-related company that requests them. Figure out how to draw the line from some company that's just going to spam the board with ads every few weeks vs. someone that is an active part of the community.
This will let people know that while they are not an official voice of the company, they have been "vetted", and so their responses can be trusted.