Is sharding screwing with rare spawn times?

I know that rare spawns have been a touchy subject lately, but does anyone have a solid reason WHY?
RNG is RNG, but between the achieves, rares, quests, and events it is extremely frustrating to try to find something that is broken - and no one seems to know or care why.
I have been putting WAY too many hours trying to get Karotka’s mount (yes I know the spawn timer & days), but we go days without seeing him. It seems like once we have a solid group of people waiting on the spawn, half of them fade away… and the rares never show up. Are the shards resetting the timers or stopping them from spawning at all?

Yes. The spawn timer is different in different shards because the rare was last spawned at different times in each shard. So basically if you get shard shifted (and sometimes you don’t even know) you no longer have any idea how long it was since the last time you saw the rare you need. It’s a really big problem, especially with the rares in zaralek.