Thanks! I actually just got to the part where I'm offered the dog costume and I just bought it. I haven't been able to trigger the scene for it just yet though, I might not have caught Shiba at the right place yet.
Welp, it might have glitched since I did buy the costume and I've visited him in all the spots since then too the point that I've not gotten any new scenes yet and I've had no further mention of using the costume. I'm in late November too.