Equally, the "red chain" is a complete enigma other than the fact that we know it was extracted from the Lake Trio. And we don't even really know what it did to Palkia or Dialga other than enraging them. We know much less about it than the Blue or Red Orbs, for instance, so why exactly the box legends got enraged and out of control as a result of the Red Chain could easily be because of an influx of evolution energy, when they were already perfect beings, and this evolution energy was extracted from the Lake Trio somehow. It's the interpretation I always took based on what Rowan said.
We don't know enough to write off his research, basically, because a lot of DPPt lore is completely unexplained save for Rowan's interpretation.
That's a stretch. I would say disregard the comment about evolution energy, that's a false start, just a random musing from Rowan showing his interest in Pokemon Evolution. That's where it starts and ends.
Why the Red Chain worked on Dialga & Palkia and why in DP the Lake Trio was able to contain one of them (but in Platinum unable to contain both) more just has to do with mythology and possibly even some symbolism more than anything else. Let's keep in mind all five were created by Arceus for specific reasons: Dialga to flow time, Palkia to expand space, and the Lake Trio to gift living beings spiritual traits. The three had their own domains and likely an advantage in their domain if one was to cross over (or to be allowed to cross over). Cyrus used the Red Chain to drag/allow Dailga and/or Palkia from their domain into ours which is also the domain of the Lake Trio (we can call it the "Mortal Domain"). Now in DP, since it was only the one the Lake Trio were able to exert enough of their power over the Mortal Domain to counteract the one dragged over. However both Dialga and Palkia together were far too strong, which is sort of why Giratina had to jump in, it's another domain master so it gave the Lake Trio just enough push to force Dialga and Palkia back to their domains.
Now that was the mythological side of things, what about symbolism? The Lake Trio represent Emotion, Knowledge, and Willpower, in the Pokemon world the main three traits that makes up a being's spirit. Now obviously Dialga represents Time and Palkia represents Space, two of the most if not the most powerful universal forces. In DP, one of them was using this great power to destroy & possibly reshape the world and not a single being could stop it. However, the Lake Trio represent the entire embodiment and those three spirit traits, and those traits working together can maintain a control over one (you can't fight against time, but you can manage your time & make the most of it; you can't manipulate space, but you can figure out how much you have and plan how you can use the space you have). But in Platinum it shows even spirit has its limit and it can't overcome both these forces when they're working against you. But fear not, because you can't always have control and you just going to have to compromise with randomness/chaos to achieve at least your base goals. And that's what Giratina represents: Random/Chaos factor as it's a being of anti-matter which is completely unpredictable (or rather we as beings of matter can't accurately predict). In Platinum, Cyrus won. There was nothing the player could do to stop his plan, the player letting free the Lake Trio was not enough. No one was expecting Giratina to suddenly appear, most people didn't know it existed, and on top of that Giratina had to choose whether it would get involved or not. So many factors that were out of the player's hand, the player had to rely on a being which represented randomness/chaos to give them the edge excepting the consequences (which thankfully was just Cyrus being taken into its domain and the player having to calm Giratina down).