My AC unit is not able to keep the house cool (77 degrees) above 94 degrees outside temp. I found the ac unit has an 2 inline expansion valves, 1 near the compressor and one in the attic at the input of the coil in the attic. Is this recommended, and could it be the cause of inefficient cooling?

You have a heat pump system. They come with two exp valves.
A standard A/C unit only has one exp valve.