UV light does not just create repairable dimers in DNA bases, it can and does rip DNA apart. Enough exposure would cause more than enough irreparable damage to kill the cell and 99% of the cell being destroyed is certainly not salvageable.
The Delta flight is cheaper. But check a bag at a cost of $25 for the first checked bag each way on Delta, and your total fare climbs to $256 -- more than the cost of the Southwest flight, which includes free first and second checked bags. Add a second checked bag for $35 each way on the Delta flight, and you'll pay a whopping $326.
Delta will no longer accept pets as checked baggage, but will continue to transport allowable pets in all cabins of service except Delta One, effective March 1, 2016. Customers may also ship pets for travel within the United States as freight through Delta Cargo.