Listen - The dealer doesn't really know if it's hydroponically grown. That's not what he's referring to when he says "It's straight dro, dawg". He's merely saying "This stuff is potent." Not "This is hydroponically grown marijuana."

Dro in the ghetto just means good shit.
And EVERY ghetto dealer calls his stuff 'dro' or 'bomb shit' etcetera. If you asked him "So you say this marijuana is grown without soil?" He'll say "What the fuck are you talking about?"

So, anyway, get right on correcting your dealer on what dro means.. and get punched in the mouth and get no weed.

Anyway, just tell him you don't need him to roll it and have him put it in a baggie so you can smoke it later unless you're friends with him or something.