ALSO keep in mind we aren't all that sure how thick the ice is on these moons... there Are concepts for melting through the ice, but how do you get the data these swimming cellphones through the ice and transmit to earth?

What if the top say 200 miles of liquid is uninhabitable by the local life? Remember the main power source will not be the sun, its likely to be the tidal heating of the rocky body under the ocean...You may only be able to look for molecules that come up from below - would they be recognizable as life signatures when we know nothing of the biology? How do we know these molecules are not from chemical processes created by unknown conditions at far deeper levels?

Such a mission will need a lander, lets say we identify a section where the ice is thin, and we know exactly how thick it is (that would be quite an accomplishment by itself...

You have a lander and land it there... the lander releases an nuclear power heated capsule that slowly melts through the ice, unspooling a cable behind it that connects it to the lander so data can be sent through the ice... which will be refreezing as soon as the capsule passes... lets say that it makes it through the ice shell, and lets say that stresses in the ice and the ice tectonics for which there is ample evidence doesn't snap the cable... It easily could be that it breaks through the crust only to find itself suspended in a super thick slurpee consistency slush... its little probes unable to move through it... no visibility... with navigable clear liquid many miles lower...

I am not saying its not worth doing, I AM saying its something so ambitious that you will need a series of missions BEFORE this mission - including landers- before you can have the data you need to even consider this...