I believe it is natural for a parent to worry about their child, especially their innocent daughter, especially on their first date! Although you worry, you have to understand that you can’t protect your daughter from every temptation in life, or every thing/one that might potentially hurt her. That doesn’t mean you shouldn’t try, but it’s something good to keep in the back of your mind. My parents let their fear rule their actions, and they ended up smothering my older sisters, which in turn made my sisters less inclined to come to them, or share information with them. It ended up pushing them away, something you don’t want to do with your child. Plus, it doesn’t sound like they have done anything incriminating yet that should warrant you to suspect them of any illicit behavior. So far it sounds like this guy has gotten good reviews from other people you know who know him and his family better than you do. I would suggest getting more opinions of people who know him, or even getting to know the guy yourself. It’s true some guys try to pull the wool over parents eyes, and play the good guy. But they can’t keep up a facade like that forever. If you (or your wife) are perceptive, you will see through an act. If the guy backs off because you insist on a “get to know you” dinner, then he is still unsure of what level of commitment he feels toward your daughter. Not necessarily incriminating, but it tells you the strength of the bond between them. That doesn’t mean insist on a get together right this instant, but once they’ve been dating for a reasonable amount of time, you might press for something like that. Or if you tend to have parties, cookouts, etc, you could casually invite him to come (a less direct approach is less awkward, and more likely to work with teenagers who avoid awkward situations like the plague itself). Inviting him through your daughter is even better. I’m sure your daughter would want him there, and the guy is more likely to say yes if it’s her who is insisting, rather than you. Then, instead of confronting him directly, watch him first, and watch how he interacts with others.
If your daughter starts sneaking around for no apparent reason, it might be time to start getting worried. If your daughter seems to show a much greater amount of commitment to this guy than the guy shows toward her, it’s probably time to be doubly worried. But for now, just wait and see, be patient, and try to reign in your worries and frustrated emotions. If you accuse anyone of something before they’ve done anything wrong, it undoes all your effort to protect your daughter. Hope that helps you