Obvious fake is obvious.
1. Nobody on the island? Even on half empty worlds there are still people wondering around or those who have missed the game.
2. People spread out. If 30 people managed to simultaneously enter the boat, they would have had to be anticipating and spam clicking the ladder. It is highly unlikely have everybody stacked up like that.
3. You are telling me bots on the Novice boat all went together and one shot portals? That doesn't even happen on the Veteran's boat.
4. You cannot consistently one shot portals. Sure, the yellow falls pretty quick to an entire team, but if a portal far away un-shields, you can't possibly kill it fast enough.
5. Claws and AGS on low levels =/= powerful.
Also, can you find a source stating shields drop fast if portals die quickly? I could not find this anywhere, and from personal experience that does not happen.