I think staying at Escorial would be the safest route. I don't know if JP ever had safe rooms built into Escorial, you'd think so after some of the attempts on the family, but if they did, Travis could hide in one of anyone came snooping for him.
If Travis went to Europe, he could fly into a Milan and then catch a train to France, deeper in Italy, Germany, Austria, Switzerland, etc. An American teen in a big city (Berlin, London, Paris, etc wouldn't draw a lot of attention. If his law firm is worth anything, they should have European affiliations they can have help hide him in safe apartments. I would change my hair, maybe even go with good wig to make it longer.
But, he could probably hide in Dallas, Chicago or New York with the help of Will's family.
I would let Curtis Buck know that Stef and Brad are watching him.
Yes, and it would be a shame if they didn't live in their assigned "yard". One of the best experiences you can have in college is that freshman experience of living in a dorm with a bunch of strangers and learning how to make it work.