Every girl I've tried dealing with who's used snapchat has tried getting a deposit to prove I'm a genuine customer.
Always the same excuse, and the same "I'll send a picture with your name in it" to prove they're genuine in order to fool you into paying the deposit.
When I point out the deposit scam is the oldest trick in the book and there's no way I'm falling for it, apparently it's my loss
Obviously I have no way of knowing for sure if that's the case with this girl, but the SP's I've dealt with on snapchat to date have been 100% consistent in that way.