There are other reasons you can be hit through walls other than just hacking. A person could be spamming at someone running past your building, a few stray shots hit the wall and enter the building hitting you. Sometimes a bubble can be seen melting if the player was killed close to the wall and it is protruding through, same can be said for floors aswell. Seeing one melting is enough for a wall spammer to try their luck and pot shot through the wall looking gor a hit marker. Someone could see you run into the building and guesstimate your position for a spam attack. This is why we dont accuse publicly in our servers or ban strait away, because most of the time its explainable (the above resons) and not dodgy play. When it is deemed to be a hack and the person banned its usually the result of hours of watching and researching a player. If you tell an Admin of some suspicious play, you cant expect something to happen strait away unless the player is damn obvious in what they are doing.
We also have a 300 max ping (maybe 280) to enter the server, if a player enters under 300 then their ping turns to shit during gameplay, they arent auto kicked so you will need to alert admin for manual kick if their ping is excessive.