Doc Scratch, man. He's really good at telling the truth in misleading ways.
[Lord English is] more deadly [than Jack]. (True)
But the danger he poses is sanctioned by paradox space. (Because everything in the alpha timeline is sanctioned by paradox space)
It is a known quantity. His very existence in a universe will mean it will inevitably be torn apart. (Jack's is a known quantity, too, given that paradox space knows everything)
But there are rules to his entry, and his grim procession through paradox space is rather orderly. (Probably because Caliborn wants it that way) The present equilibrium has accounted for him, and will continue to. (Same with Jack, in fact. He hasn't said that Jack isn't sanctioned, nor that he's accounted for.)
Jack however is a loose cannon. He will not stop until he destroys everything he encounters. (But his being a loose cannon does not say that he's not accounted for or sanctioned.)
Additionally, his existence is your responsibility. (The same can be said for English.)
Refusing to venture out to destroy the sun in no way spares anyone from my master regardless. (True)
It is certainly true that destroying it will end my life. (Hee. True.)
And it is certainly true that The Tumor you will deliver to its location has enough power to destroy it completely. (But he didn't say that it will.)
But it is not the only way to kill me. (Apparently, Hussie's presence will do that. Or just living long enough for LE to explode out of him.)
It is simply a way I have suggested to you, which doubles as a way to disarm Jack, should you choose to go through with it. ("It" referring to destroying the green sun, which is not actually really possible, but the statement is true regardless.)
Man, what an a-hole.