>>11721196 (pb)

If I recall my DNS correctly (it's been a while) the MX branch are mail exchanges, i.e. email servers. The DNS branch shows which DNS servers they use (CloudFlare). The A branch are the actual webservers. What you are seeing as a belgrade server is just the name assigned to it, though geo-ip is placing it in Serbia that only means the ip has been assigned to an ISP that provides services to that area. Where the physical server is located could be anywhere but is probably in or near Belgrade unless they are using a VPN to route the traffic elsewhere. There is no way of knowing from this data what the server is/was doing. Most likely there is/was an office in Belgrade and that is/was the webserver for it.