First off, I absolutely love your curious, methodical approach to this dumb bug!
Second, and I'm almost sorry about this, I've already fixed this issue for the next release - whenever that may be. Turns out, it just came down to my lack of scripting knowhow. The scripts for the NPC gifts for both Tindle, Leguis and Tadish all have the same oversight, which is that they simply don't really account for nicknaming, so yeah, Very Strange Things will happen indeed. It should work as intended for the next release, though.
Actually, the game should register night-time only from midnight to noon, and day-time as ranging from noon to midnight. It's a little dumb, I know, but try again between midnight and noon. If it still doesn't work, I'm not sure, might be an emulator issue - the day/night evos should work on most emulators, though.
Yeah that's a bit of a dumb oversight on my part. It's listed in the "Known bugs or issues" section" on the front page and will be fixed in the next update.
I haven't seen this until now, but thanks a lot, I'm glad that you enjoy the hack!