Sorry, we're full up.
Kind of my answer.
The real approach would be
1. Does LSU need the player or is the position stocked to optimum level.
2. What's the relationship with the kid? Were the bridges burned?
In these two cases, I'd say the bridges are probably burned with Davis. No so much with Collins, who is the brother of a likely future LSU commit. If Collins wanted to come, say, after the fall semester, I think LSU would have taken him. It'll need safeties in two years. He could have helped.
Now, if he has to sit two years per SEC rules, no way. And if, say, Alabama got a Penn State-type NCAA sanction and he was allowed to transfer and play right away, LSU would have taken him in a heartbeat, I think.