As you say ......... Most Bond aircraft are fitted with the Bristow system of AFDS, but the 225's are coming with the Eurocopter version of the same. I assume it is fitted under licence but not sure - Its a basically identical system.
Either way, depending on the final outcome and investigation, I am not aware of any aircraft ditching previously, without the floats already inflated. If it were the case that this was an unintentional ditching, and this aircraft remained upright with floats deployed, that would be a huge testament to the system.