Sentinels is already in champions

the only reason is praccing to the Champions

yup, if a team is eliminated by SEN they become unable to get any points and that sucks, but that's not really a problem since NA tourneys have double elimination and SEN are probably not losing so the second best team can always make a lower bracket run and get their points ( it doesn't matter if SEN have 1000 more points than the second place, the top 3 from NA qualify for champions so every team's aim should be getting a high placement, they don't need to be equal or better than SEN, they just need to be better than the other teams )

If they win Berlin, 2nd NA team (circuit point) will get the 1st position that will get NA another slot for champions and ofc the fame and money and maybe practice

if they win master 3, will have a guaranteed place for the third place in the circuit points from NA

In the early days, T1 didn't play in many tourneys outside of the Ignition Series tourneys and they fell behind the rest of the competition so I don't think Sen sitting out all of the tournaments until November would be a good idea... Plus if they do play it's better for NA since Sen playing means NA would have a better chance of winning at Berlin and if NA wins Berlin, NA gets 4 slots instead of 3