Allow people to:
1 Skip one queue for free, without repercussions each day (then you move on to the standard 3 LP > etc.)
Each day?
There's 10 people in each game.
If you assume everyone plays 10 games a day and feels like dodging 1 of them, then the odds a game will go through is 90%^10, or ~35%.
65% of your games will never start because someone dodged in that scenario.
Considering a lot of people have a job, school, or can't afford to spend ~6 hours every day playing: that's probably a generous amount of queue-dodged games as well.
2 Skip one queue per promo series (doesn't stack with 1)
Again, it's 10 players per game: not just you.
To get the chance a game will start up to 90%: you need to limit the chance each person will dodge to 1%, as 99%^10 = ~90%.
There ya go, trolling is suddenly way less of a problem.
If less than half of the games actually start I really doubt such a change would have any effect on trolling.
Rather than a troll having leverage on games because you can't dodge and they're valuable, trolls have leverage on games because they never start and are valuable.
Queue-dodging would become an epidemic with such a change too.