1 Yes

2. Yes but no. You get pack as long as you are in the Saturday fight, for both GNW and XGNW afaik. And in case of XGNW, there are only 8 selected so you can't be disqualified in Wed.

Unless you expect to at least win one round on Sat thou, it might be better to opt out, you will get more seal scrolls that way. But if you think you can win at least one round, Xserver might be worth it.