@Psubond um, ok... so. I tried your suggestion and it did seem to work at first. After the first portal game progression was unstuck and it granted two dots of battle pass XP. So now things start to get weird.
I switched back to do normal AoW games and at the end of the first match my progression bar pops up and I'm missing the two dots I just received in Portal minus one more. So I gained two dots to fix it just to turn around and lose three. SNAFU can't even begin to describe this...
I tried another game of AoW and this time it granted me one dot of the three that it took away in the previous match, not all three just one. From this point out I gained and lost XP in AoW randomly until I completed all the XP needed for level 97. At that point I said screw it and used the rest of my earned Boins to buy my last 3 levels to reach 100 before it started going in reverse on me again.
So that's where I'm currently at with it. I have all the unlocks to 100 now but my Season 1 Badge is still stuck at 866 points and has been there for a very long time without progression. I doubt I'll get the badge completed before the end of the season if they don't get this all sorted out sooner than later.