Manipulate someone question

Hi all,
we had the following situation in our game: my hunter wants an hospital guard to follow him down a corridor, but the guy is busy drinking at a bar.
So, I tell him there's a fight in progress between some inmates and ask him to come along to stop it; then, I roll the dice to manipulate him ("Once you have given the target a reason, tell them what you want them to do and roll +Charm.")

I get a 10+, which means that "they'll do it as long as you reward them as promised.", but I hadn't promised the guard anything in the first place...
How would you narrate the result in such cases? Would you simply ignore the reward part (as we did in our game)?

Thanks!
Girolamo

Yes, in that case he should just do it. However, in this case the guard might get angry if there wasn't actually a fight going on when you got there.

And, in fact, he was confused, but he didn’t have time to get angry, since Natsu – Girolamo’s PC – hit the policeman with his katana’s hilt, knocking him down. ;-)

Thanks for the answer.