As far as I know if the water main is controlled at the end of round 1 it will carry to round 2. You only need to wait for the healers to do their standard heal and control their Kurenai (most of these teams will have her) so she doesn't clear the main. Though if they happen to have 5k Madara, then you are pretty much done for :)

well dodger can be handy in this matter for shark bomb.

or kurenai passive for counter chaos.

an for double healers,its hard to tell who's you are reffering to, since healer like normal kabuto or normal sakura or shizune which are not matter at all.but for A++ im assuming that's sailor sakura with water main. then mostly they will use poison attack not the experiment talent. so which cancer water type that you are reffering? its the poisons or the chaos.if they use han with water main and sailor sakura than mostly they will go with poison type, which mean the main its self are not on pos 1 majority, maybe on pos 2. so there are no reason for ur pos1 cant lock her down and canceling the shark bomb with acupunture/immobile in build pos 1 mystery or from ur line up chases.unless... your bp gap are too wide.hope that clearing thing a bit.