Navy is much smaller than 1969
I hope they've talked to the Navy about this. The Navy is *way* smaller than in 1969, and of course our carrier battle groups are very busy (not that they weren't then -- flying missions over Vietnam).
Pulling aside a bunch of ships for a primary recovery fleet plus contingency fleets scattered around will not be a trival thing.
Unless NASA is going to buy its own ships, which is pretty unlikely.