Perhaps they had a falling out and that’s the main reason he’s gone off? Broken heart? Thought they were going to hook up on holiday but she ended up with another bloke? Perhaps that lead to an argument and that’s why he decided to leave the club and get away from his group of friends. Maybe the conversation in the morning was him calling to apologise for the argument and saying something along the lines of “don’t worry you won’t see me again
Occam’s razor being what it is, I rather suspect personally the phone call was as simple as reported - he had no phone battery and was lost so felt he should send her his location.