OK, look pompey you been around here for 2 years now; you should know by now that it's simply courteous to convert hands. You should be bloody thankful that anyone at all bothers to trawl through it looking like that. So ffs convert it in future and don't be such a nob saying no like that. I think the phrase you were looking for should have been "Sorry, point taken, will do next time."
As for whether it's good collusion or not, well, as I'm not a colluder, expert or otherwise, I was merely voicing my opinion about the way in which it seems they're going about it. And in the long term it seems to me that their strategy for working together is a bit meh. That they've chosen to collude at this point merely makes it obvious to any observant opponent what they're doing when they'd be much better off picking their cooperation plays with a little more care and a lot better expectation of success. Obviously, it's not such a great call for you specifically in this instance, but as with all aspects of poker, it's all about the long term, and learning and adapting based on past experiences. So, as it seems that the site in question won't do anything about them, you can use the knowledge of their teamwork and their blundering strategy to your advantage in future spots. And if you can't do that then simply avoid games in which they both register.
And as for complaining about collusion in DoNs; every 2+2er knows about it, or at least they should do. And we also know that sites differ in their views and in the actions they take in response to it. So don't whinge about its existence, or the site's reaction, because you should already have factored this into your decision to play where you do. You should merely consider collusion as part of the cost of doing business and factor it into your expected returns on the game.
GL