Yes you're right, I'm afraid that if you don't reach the 100 followers before Saturday you'll be skipped from this round. I agree that it's not healthy for the people who just created the account to grow it artificially in just a week not to be skipped and I think a 2 weeks deadline would've been much better but this is the way they've decided so have to comply.
On the project's Discord channel there are a lot of people sharing their links to twitter in the off-topic sub channel, if you need to grow your followers base you can go there and follow the links for a follow back; it's much a better solution than using popular hashtags that eventually will make your twitter tremendously spammy, but I don't know whether it will be enough only with this.
100 Followers is easy, Its a good additional rule since it will create more activity for the part of airdrop participants. Having more followers will create more exposure for Staker token and this will eliminate lazy airdrop participants.