Have any of those match had a longer than 1 min wait time? Because if it have, ALL the other rules get thrown out the window and you will fight the first other person who also have a 1 min+ waiting time.

The reason I ask is that you sound low level, and problem with low level is that there aren't that many of you (leveling up become progressively slower, so people tend to cluster in highish level. There are tons of high 80s and low 90s in higher servers. Mind you, I'm talking about active player who actually do masuri. The oceans of inactive lowbies don't count). And when there aren't many of you, you won't get a regular match very often and will tend to run into the overtime which gets the boundless matching. This won't go away until you are at least in the 80s, unless you are willing to repeatedly cancel matching as it get close to the 1 min mark.

Even in "later" server cluster where 90s are rare, the cluster tends to be around 80s for the earlier server of your cluster, where you get more or less the same effect if you are below or at mid 70s.