It's really not an issue. Bosses respawn on variable timers and with something like approx. 4-7 possible spawn locations. People do know the value of those variable timers, but it means you'd need to camp them for 48h hours or more straight nonstop to make sure you catch it. And even if you spread out 4 alts across all spawn locations, chances are you still won't be covering all the spawns. So sure, there might be a little drama over this every once in a blue moon, but it's really not an issue at all.
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"We are Kami. We are here to be you. We are many as you are of many minds. We are one as you are one in Ma-Duk."