Because of Ike’s name dropped, this means R’s letter was written while Ike was still alive (and I’m certain R would know when a volunteer die or is actually alive). While we don’t know how old is Ike, I always assumed Ike was around Lemony’s age or younger, since I could have sworn Ike was mention by Lemony in the Beatrice Letters but I think I was imagining it.

In any case, Ike and Kit were potentially close to one another to where Kit could trust Ike and possibly treated Ike as a younger brother (especially consider Lemony is on the run and Kit never saw Lemony again). Kit and Ike became close enough that Ike was 100% ready to keep important papers no questions ask, or little questions ask. 

Gregor is dead at this point. It’s not stated, but there’s a good chance Kit was involve by ‘ordering’ the hit because of her criticism. Ike could have connected the dots and felt betrayal by Kit, who he saw as a friend and possible big sister figure (especially if Ike and Gregor’s relationship became rocky due to the Medusoid Mycelium and Ike potentially turning to Kit to ‘replace’ Gregor).

Ike could have turn down -or ignore- Kit’s letters or phone calls about the letters. He could be ‘retired’ at this point, but Ike could also feel bitter and upset Kit wants Ike to stick his neck out for her and her brother, yet Kit thought it best to kill Gregor -Ike’s own brother- even after her fail warnings fall flat.

And Ike most likely broke all ties with Kit due to his loss, forcing Kit to send the letters to the dairy instead. 

Compare/Contrast:

L: What’s the matter with your hand?

M: No, that’s not what M meant, L. “At hand” is a phrase which here means “the matter we gathered to discuss”. As you get older, these expressions will be easier to understand. (The Unauthorized Autobiography, page 37)

“There is a theme restaurant located on the main street called the Anxious Clown. The food is dreadful, but I’m afraid you’ll have to eat there until you find a waiter who says to you the following sentence: “I didn’t realize this was a sad occasion.” That will indicate that he is one of us.” (The Unauthorized Autobiography, page 97).

WAITER: I didn’t realize this was a sad occasion.

MAN: Stop saying that! It’s not a sad occasion! I’m having lunch with my sister.” (The Unauthorized Autobiography, page 135)

Because the second L in the transcript needs someone to explain the phrase ‘at hand’, Larry may be the youngest SBG if one exclude Fernald’s from the SBG (Larry is second youngest in meeting given the second R says she’s nine years old). In the third passage, that happens post Wide Window, possibly around Jacques’s death in the Vile Village.

In any case, Larry and Jacques knew each other. Given the implication Larry is potentially the youngest SBG, Jacques and Larry could possibly see each other as brothers (a bit like Kit’s section; Lemony is on the run and Jacques never saw Lemony again and could have thought he died) and Jacques is ‘projecting’ Lemony onto Larry (both are ‘L’ after all).

Because of their possible sibling-esque relationship, Jacques 100% trust Larry with helping Lemony -his own brother- escape the country, and Larry kept his end of the task. Do Larry and Lemony personally knew each other? I like to think that the two knew enough of each other to give each other some respect, given their connection with Jacques. 

While a minor character, Larry is an active volunteer by the time of the Wide Window, as he says the coded sentence and nothing came out of it. He’s still active when Mr. Poe and Eleanora -two perfectly alive siblings- come to the Anxious Clown for lunch together.