That was quite an unnecessary extrapolation from the TS's point. I dont belive he was saying that all he needed was takedowns, just that he's trying to consider in which discipline to study takedowns.
Now for my two cents. I really believe that you should find the solution which is the most inclusive. You really do need exposure to everything you can get your hands on. That being said, you probably dont have the time to study wrestling, sambo, and judo separate from each other. Sambo is an amalgam between many eastern martial arts including Judo(created by the first two european blackbelts in judo), and slavic folk wrestling. I would say that for a single class, you might get exposure to more takedowns and theories in sambo, than the other ones. If you're in toronto, you have a good sambo school there I believe. You're not going to be as good of a wrestler as someone who trains pure wrestling. You're not going to be as good of a Judoka as someone studying purely Judo. But for an MMA context, it would seem to me that you might have more to offer in terms of what techniques you've encountered than just a wrestler, or just a judoka. There's not going to be too much that's too foreign.
So long as they believe the old russian anecdote "when the training is hard, the battle is easy" it should be a good road to stroll down.
My two cents.