Yes, our attic is now sealed from the ridge down to the 2x6 plates with 3" of closed cell polyurethane foam. Where we had overhangs, there were knee walls from the outside wall up to the roof rafters. Any spaces were covered with roofing felt to create a surface for the foam to transition from the roof sheating to the knee wall.
To my knowledge, the code does not require covering the foam in an attic space that will not be used for living space.
Regarding the wires, there are some short lengths (up to 2') of romex that were foamed in. Should I be concerned?