Okay, you do that then. Walking a fine line is his choice to do so, but it might end him up in some light trouble. It was a warning that it could cause him problems. Which is very true.
If you want full clarification of what you want to do is okay, please contact
sales@vbulletin.com and we'll make sure to get you an answer.
However, generally the copyright must be fully intact, and plainly visible.
And because I'm a fun guy who likes to have fun, screen shots are totally proof