Follow up to above message. Hopefully person who was cause of group shut down (posting, not reporting - those people done what was expected) and apparently my account being limited, become miserable because of their inner suffering.
Not sure if telegram administration ever reply on my email about those limitations, but till then do not even think I will open second group any time soon.
And to fellow admins who have own groups, good luck. Looks like without limiting users to post anything or having 24h group monitoring, you risk a lot. Glad I just got account muted instead banned, but still.