I'd say the only other thing you could've done was cow call but it sounds like you did everything the way you should've. If the cows spooked then they proabably either winded you or saw you or your partner. Even with the best scent covers you still breath human and they will sense it eventually. Just another story of how you think they'll do one thing and they do the opposite. Chalk it up to experience and try a different call next time. I don't know how you answered him, aggressively, passively, full bugle, chuckle or not but they all mean something different. A lot of times the best thing to do is imitate him. One thing's for sure something will work one day and something completely different will work the next day.