Transactions need to be confirmed to count.  So 8min is getting to the point where it is too late to do anything.  After paying everyone out 1Excalibur needs to advertise the address to recover.

I expect investors will push their TX out by pumping more in, so it runs down to who can afford to keep playing.  Anyone who has yet to play are the big losers, you can't win if you don't play and the longer you wait to play the more BTC will be required for a payout.