Total Games: 40177
Games on Nordwind: 2854
Odds to get Nordwind: 2854 / 40177 = 7.1%
Games on Lienne: 3905
Odds to get Lienne: 3905 / 40177 = 9.7%
So what are the odds you get Nordwind 3 games in a row?
So what are the odds you get Nordwind 5 out of 6 games in a row?
So what are the odds you get Lienne 3 out of 5 games in a row?
If your focus is about playing the maps "in a row", hard to tell if Relic servers have some issues. Might be. But the question itself is biasing the analysis. You show 8 data points, yet sometimes neglect some of them.
The chance for someone having your vetoes (and assuming the other players 100% conforming to the general map frequencies, which we can't do but the stats you show are the best assumption we have) playing 3 times Nordwind in a row is 0,5%, for Lienne 0,94% (the starting point of the series doesn't matter, so it comes down to map_chance^2).
For playing Nordwind/Lienne X times out of 8 games, the chances are 8,1*10^-5% and 0,03%. Given we look at ~40k games though there are a lot of chances for this happening too, especially for Lienne.
The issue is that if I look at my last 3v3 games, I find 1 Whiteball, 2 Redball, 2 Wineken, 2 Rhzev, 1 Hamburg, 2 Rhine. Vetoes slightly change depending on Axis/Allies, but usually they are Oka, Steppes, General Mud, La Gleize.
My data has as much validity as yours. They are both singular obersvations, but mine seems to be totally fine from what I can tell.
So there are two options: Either Relic servers are indeed screwed and for some reason biasing Nordwind/some maps/generally favor streaks. Or you were just playing with a player base that had unusual vetoes and was not vetoing Nordwind as often as the average player base does.