Of course she will, didn't you watch OP ?
As for the bosses, it was said that nothing respawns, which means the XP points are also limited, just like he said, in the first episode, but the progress might not be meant as selection process. I'm also not quite sure if the players really die, even though what was said already is quite logical and stuff, I think that there is some sort of backfire on the players forcefully logged out, it could be a coma, but I'm not sure if they really die.
The thing about Beta Testers is that they have a certain advantage, but only because they already know stuff, that doesn't mean new players are in any way weaker than Betas. New players learn fast, and the only ones complaining about beta players are those that put the least effort into the game, lets call the super casuals, I seen this battle with the boss 2 times, and that guy that complains about beta's practically didn't do anything, he was standing behind. Talk about Hypocrisy.