Hey.
I generally know there are some things that can happen, but having same rival in oly for 6 times in a row is at least weird. The probablity is (1/4)^5 (5 players signed (5-1), for 6 matches (6-1)) so its 0,097% that you meet same guy for 6 times in a row. I know that can happen, but things like that just keep happening. I had around 15 fights today. The first 4 or 5 fights were with same guy. Then I had some diffrent players. Then again 6 fights in a row with same player. I wasn't skipped for a single time (also only 3,5% chance for that, (4/5)^15) . Also when some1 is skipped, it's very likely that he will be skipped again. Some people are skipped 3-5 times in a row. The probability is also sooo low.
I know this issue from other server. Around 70% of fights I had overall was with the same player (WTF?). It was also L2j server.