It seems you don't actually know how the TB in OSRS works any more than I do. When Jagex updated the GFX to be the purple orb, they added a new projectile GFX for when you splash too, as I managed to locate
here. Anything different happening with half TBs I'll need actual confirmation of. Also, the old TB projectile GFX was replaced with the ballista contact GFX, so it no longer exists to use.
I haven't been able to find anything online about dropping items working differently in the Wilderness opposed to other areas (3 minute total time, last minute shows for everyone).