Okay any predalien design is gonna have some similarities. But the mandibles on ADI's predalian are off to the side, surrounding a regular alien face and the dread are long as hell and coming out to the side. Dave's design actually makes the mandibles part of the face, like they should be, and doesn't put my emphasis at all on the dreads. The only similarity I see is the top of the head and the bulky tail, but what are the odds that they'd want a bulky tail anyway to make it look threatening.