I believe this is a CYA moment. In reality, they sent EJ on her way to pack and get going on the trip they all planned. That would be hard to do if Gabriel was at the Smith's house and needed to be passed off to Logan the next morning.
IMHO - Jack and Tammi knew exactly where EJ was going. It just didn't make sense to keep Gabriel at their house for the plan to work.
Again, JMHO.
Mel
Exactly.