I'm nowhere near a lowball expert, but I believe your intuition is right that drawing two cards is poor play because it's simply too many cards to draw. In the situation of 3 players doing it, it's even worse though (without knowing the full context of the situation from the book) because all 3 players are playing a multi-way pot with weak holdings.
The worst of all play, though, is from the 3rd player because they have the knowledge that the other two players are weak and chasing. In other words, the 3rd player would have a good shot of winning by standing pat on a mediocre hand, trying to dodge the other players' draws, or even by drawing one with the intention of bluffing if they miss. Instead they are joining in with a speculative draw which is also transparent to the other players.