Is this RV to long in the back to launch 24’ boat.

Brain,
I would be very cautious. If you are launching in tidal water and the water is down, the rear could end up on the slippery part. There are lots of Youtube about this......

Are you launching an little motorboat? Those are easier.
Boats that have masts are usually more difficult.

Have you considered the possibility of getting front hitch installed?
The drive wheels are on the dry and the driver can see what he is doing.

Matt