I would get a court approved visitation schedule, too. I have the same issue - sending off my 7yo son into a "black hole" this summer. Nothing is arranged, I don't even know where he lives or works (of if he even works), I don't know where my son would be staying, where he would be if stbx is working, etc. My lawyer advised not answering any more demanding text messages about the visit because it needs to be approved by the court. We have no formal visitation agreement yet since stbx has dragged his feet about EVERYTHING in this divorce. yet, he wants all the benefits outright.
Don't get me wrong, I want my son to see his father. I also want to make sure he's safe and well cared for.
Your daughter telling you what she's doing at 13 years old is going to become an even bigger problem at 16 years old. That needs to get nipped in the bud. She can't decide that she's going off on a trip without your permission. If she does those kinds of things, tell her the police will return her to your home as a run-away. Would she maybe listen if the police were involved? My heart goes out to you. I can see myself in this same situation in 6 years or so. It's really tough to keep a reign on kids these days because our culture tells them they're entitled to the world. Parents seem to have no effect any more on kids. It's sad.