There are a whole host of things that come with twin engine helicopters, if they are treated as such properly. More than 5 hours of training is needed to come to grips with the complexities of single engine failures, especially if Category A procedures are included. AFCS operation also takes quite a bit of getting used to, and the AFCS and autopilot need to be used all the time, not just as a crutch when things aren't going well. More than 5 hours of training for someone new to a complex multi-engine helicopter is definitely needed.
A good case can be made that the relatively small number of takeoffs at scenes compared to total takeoffs would allow Category A performance to be waived for scene takeoffs, or at least some other guidance given on how to best use the OEI capability if needed. (Sorry but this isn't well stated- the caffeine hasn't kicked in yet this morning).