personally i have never seen anyone use 'foam emmiters' i have never heard of them.., doesnt mean they are nor there.., i thought wake was to do with turbulence and frequency added in its (frequency) Y direction (my memory) and magnitude all tweaked.., foam i thought was some thing like a ramp in the ocean shader??
all sounds like you have over complicated an already complicated (of sorts) procedure
hopefully someone in the know will help and we will both learn
you can pulll down an example ocean and look at its settings.., you could tghen make it live.., draw a motion curve (curve) on it.., make it unlive.., and the animate you boat along it.., if i had time i would check to see if you had to make it a colllision object to get the wake happening..,
all this just happens to be something im interested for a short film im making.., i want to do that trick in Matrix when he puts his finger in the mirror and his finger and the mirror sort of join and become liquid..,
same thing you want sort of.., soft bodies.., but in this case.., with springs
take it easy and life will be easy