1. Delta isn’t going to go under - they are too big to fail. At WORST they would end up merging with someone else but even that is highly improbable.
2. In either one you could probably get LAX fairly readily.
3. Interviewing does not mean you are going to get the CJO and even canceling the CJO as long as you gave them lead time enough to slide someone else into the Indoc date would not leave any sort of indelible stain on your record either.