Can LCS and Dynamic Que co exist? If so, How?

Since 3 players max can que together at higher elo's. that makes 5s teams, well.. not a thing, considering LCS is all higher elo players how are they going to BE lcs if they cant que together? How does one practice 5man team play without 5s team play? That also makes getting INTO the lcs literally impossible since there is no 5s teams anymore.