If the Giants keep the pick, they have to be taking a QB. There's no way around it and anything else just doesn't make logical sense.
Assuming the Giants really don't want a QB, they can accumulate extra picks by moving down just one spot in trading with the Jets and guaranteed they still get exactly the guy they want at #3. The Jets will/should make that trade to lock in a top-2 QB on their board because good bet that Buffalo/Denver will come knocking on the Giants' door for that #2 pick.
Last season, the Bears traded two 3rds and a 4th just to move up from #3 to #2. Perhaps, that's what the Giants can expect here as well if they were to trade with the Jets. Even just an extra 3rd would be a win for the Giants.