Every time you try to get them do something for their own good, they figure you've got some sort of a hidden agenda.
This episode contains examples of:
Batman Gambit: Sheridan's whole scheme to get the League of Non-Aligned Worlds to allow the White Stars into their territory.
Bat Deduction: Sheridan basically throws a bunch of things out there and lets the League ambassadors "figure out" what's going on. Of course, it doesn't matter what conclusion they come to, as long as they think it's something they need Sheridan's help to deal with.
Big "YES!": After his plan succeeds, Sheridan walks into a transport tube expressionlessly, but as soon as the doors close he lets one loose.
Entertainingly Wrong: The League's final conclusion: that there is some new enemy which can only be detected by the White Stars. Therefore, we must have the White Stars protecting our territories to keep these unseen enemies out. To that end, we will force Sheridan to deploy them along our borders, giving him any clearances he needs, so he doesn't have any excuses. And through it all, we will remain blissfully unaware that we have done exactly what he wanted us to do.
A far less fortunate case regarding the Religious Caste subplot; thanks to incomplete information, the members of the Religious Caste think Delenn is about to sell them out to the Warrior Caste. By the time they learn how wrong they were, they've already rigged a device to kill everyone aboard. Thankfully, Lennier overheard their plans, and managed to stop it before it became lethal to the entire ship.
Getting Crap Past the Radar: Unlike the Drazi, who have beady little eyes, the Centauri have "great big eyes, and great big scanners, and great big..." Well. (Note Londo is gesturing to the sides of his torso as he says this; where his people's tentacles are located).
Happily Failed Suicide: Once the religious caste members realize Delenn is not going to allow the Warrior Caste to rule, they rush to turn off the valve releasing the toxic fumes into the ventilation system. Fortunately, Lennier got there and turned it off in time.
Suspiciously Specific Denial: "Nothing happened today in sector 83x9x12. I repeat, nothing happened." This is actually an Invoked Trope; nothing did happen, but Sheridan wants the League of Non-Aligned Worlds to think something did as part of his Batman Gambit. Poor Ivanova.
What the Hell, Hero?: Lennier to his fellow castemen after thwarting their suicide attempt: "Have we fallen so far that we can no longer trust ourselves?"
Ivanova starts into one towards Sheridan after he asks her to insert some creative misinformation into her newscast, but Sheridan's on a roll and convinces her to go along with it, assuring her that it is 100% true (which it is.)