In the back and forth "coffee" IG posts, he talks about looking forward to backroads, cool nights, warm coffee. If that doesn't sound like a road trip and camping to me, nothing does. If they've been staying ahead of the AA's, keeping to backroads, and making minimal public contacts for gas and supplies, it is possible.
Around 1999, Andrew Cunanan hid in the middle of Miami for two months despite being on the FBI's most wanted list and having his face plastered all over the national news constantly. So it can happen. But Cunanan slipped up eventually (he pawned something and wrote his real name on the pawn slip instead of his fake ID name.) TC will too.