Just for the record, I'm not Fizzer; everything in this post is my best understanding of how things work, but I can't promise 100% accuracy on everything I say here.
I have a few questions: Is there any way to follow up on my report and find out if any action has been taken against canadiensnextyear? Obviously it is an account set up to benefit some other account. Is there any way to find out who the beneficiary is, and if so, will action be taken against him?
There is no possible way for you to determine if your report resulted in a warning; those are invisible to everyone except the player involved. While I can't remember Fizzer ever having confirmed this, I strongly suspect this is by design. If your report will result in a long-term (or permanent) suspension, the account will automatically surrender in all its on-going games. I'm not entirely sure whether that also happens if a short-term suspension is issued. However, in the case at hand (the linked game has direct-boot set to three days), you can still manually kick him.
Accounts which are currently
suspended are marked as such on their profile page (I think including the expiration date of the suspension). Once a suspension is lifted, no permanent trace of the suspension remains on the profile.
If the culprit is found will this awful game be deleted? Meanwhile it drags on...
I don't think any games are deleted, ever (exception: map testing games, because retaining those would require storing each and every single version of a map on which a testing game has ever been played; those games are
deleted, but only(??) because of practical reasons). The best you can hope for is a vote-to-end.
I suspect this "playing-to-lose-to-benefit-the-other-team" happens a lot. Are there safeguards against it?
Please do keep in mind it is incredibly difficult to reliably tell the difference between an utterly incompetent player, someone who has a bone to pick with you (and doesn't mind recording a loss on his own record if he can annoy the hell out of you in doing so) or someone who's actually using a second account to spy on your team.
That having been said, I'm sure Fizzer has some tools in place to make it easier to catch (and punish) offenders. In order not to help (potential) cheaters, I think it's better if I don't describe any such possible tools (and hope everyone else will also refrain from doing so!).
The only safeguards I'm aware of are the option to report people, the possibility for Fizzer to temporarily or permanently suspend accounts and your blacklist (which will prevent most (but, for practical reasons, unfortunately not all) cases of you having to ever again deal with such a player).
One question about that particular game: are there any other players in it (preferably on the other team) which you've played before? You could private-message them and ask if anyone said something in their team-chat which they shouldn't have been able to know, that would be a possible indicator of foul play. If that's the case, it might make sense to also report the account you suspect to be canadien's alter ego.