No one will surely join up this team.If i am that smart person i would rather solve it for myself and will get that 300 Bitcoins on my own without the need of dividing into other people.
Sounds too greedy but if you can actually do it on your own then its normal for people to choose up that way and besides you wont even have the guarantee that you would get the shares once the prize is being distributed.
So, if the puzzle had been solved by your team i assume you are the one who would collect those coins? No one would trust you up.
Except you are hardly gonna solve the really hard ones alone, also, it's part of the fun to do it with someone else. Some of these puzzles take years to solve. Let's see you keep going when you feel you are stuck.