Actually you are wrong. This is how currently works.
Let's say 5 rg and 3 fk register.
RG FK
Player 1 accepts Player 1 accepts
Player 2 declines or not respond to invite Player 2 accepts
Player 3 accepts Player 3 accepts
In this case player 4 from rg side will get invite, if player 2 declined, he will get it immediately, if player 2 did not respond to invite, he will get it after 20 seconds. If player 4 don't respond either then player 5 will get invite on last 20 seconds before bg starts.