Ok so we are struggling trying to find the source of this bug, we have applied a lot of shit to try to identify it, updating windows sockets and what not, also a plugin that's identifying how many packets gets sent and received from players to server and vice versa.

The thing is this bug is not general, for example only 1 player can see people bugged like shown in the video, if some other guy would for example get in that area just a seconds later he would not necessarily see these same people bugged "standing still" on his screen. We thought that it's in movement handler cpp files of source but apparently is not or we have settings wrong. Any idea and help is appreciated.
It's also not region related, we thought it's duplicating people's location at particular region and then not removing them properly, but since it gets bugged randomly from player to player it means that it's removing properly, or at least removing in general and some people might not get the information that user is already removed from location where he's bugged visually.

Video: