I didn't check all of them, but for the ones I did I couldn't find occurrences for some of those numbers anywhere in the game. All I can guess with just the information you've given is that you didn't convert from hex to decimal correctly.
I can go take screenshots, if you like. I highly doubt I didn't convert it correctly, considering I was using a hex-dec calculator.
Something odd I DID notice about these strings... They only contain 7 characters, as opposed to all of the others (that worked) containing 8 characters. I also noticed that, in-game the parentheses were off on these specific things as well.
For example, one of the comments that was made in game that worked: 6:(1a3a45)
One that didn't: 6:(1a3a45
No parentheses on the end.
Also, semi-related... We have to be careful with translating comments. The speech bubble on NPCs does NOT get bigger to accommodate our longer sentences.
EDIT: Byyyyy the way, these are all comments you can find in Bee Village. Right click an NPC to get the comment I'm referring to, for the NPCs posted above.
Well if it's not showing the end parenthesis then there could be some other characters being cut off, and so the number you're getting is incomplete. Unfortunately there's really nothing I can do about that right now.