player name not on recently met list

Tonight I was playing and tried to report two cheaters. If I right clicked on their names it took me to the friends menu. After the game ended I went to the "Recently Met" list and cheater names are not there either. These guy had a level of over 1700, and even if I looked for a player with such a high level, you cannot find their accounts to report. Looks like these cheaters have some sort of hack that allows them to stay off the report or player list. Is anyone else finding the same problem?