Ditching?
From the Robinson web site,
here, you can download the latest POH Supps section.
Under limitations it states that the aircraft is not certified for ditching with pop out floats. I believe that if you read the Part 3 Emergencies and consider their definition and actions for ditching that makes more sense. Basically, let the pax out, fly away and roll off the throttle putting it into the water. My opinion is this is Robinson speak for don't ditch, just inflate and land.
Also in this link you will see that the aircraft is stable in 12 inch wave height, crest to trough.