Okay, I did a Google search on this, and come to a Nico Nico Pedia page.
削除状況
GUHROOVYの会社としての名義は「有限会社エー・トライブ」であり、削除動画の権利者名もこの名前になっている。
which I think says something like
Causes of deletion
As a company of GUHROOVY, "Limited Company A Tribe", deletions of videos will be under this name.
It seems like some kind of maker of electronic music.
I think djchucky could be the actual e-mail.
EDIT: New information!
On Wikipedia, I found this:
CDショップの店長は、彼らと同様に家庭用beatmania IIDXに楽曲提供を行っている国内有数のガバDJであるDJ CHUCKYである。
I won't translate, but it's very plausible that the e-mail would be djchucky if it's mentioned in the article...
