Here are the standings with 18 games remaining:
W L Pct. GB Valpo 12 2 0.857 0 OU 11 4 0.733 1.5 WSU 10 5 0.667 2.5 UWGB 8 6 0.571 4 UDM 8 7 0.533 4.5 UWM 7 7 0.500 5 YSU 5 9 0.357 7 NKU 5 10 0.333 7.5 CSU 3 11 0.214 9 UIC 3 11 0.214 9The difference between 1 seed and 2 seed is largely gone this year because the tournament is at a fixed site, but that never mattered to me for this analysis so I'll still cover the 1 and 2 seeds separately.
Only 4 teams (Valpo, Oakland, Wright State, and Green Bay) have a shot at a share of the regular season title, but only 3 (Valpo, Oakland, Wright State) of those 4 teams has a shot at the 1 seed. If all 4 teams finish 12-6, Oakland wins the 4-way tiebreaker because of head-to-head competition: Oakland 5-1, Wright State 3-3, Valpo 2-4, Green Bay 2-4.
Valpo can get the 1 seed by winning at least 3 of their remaining 4 (Oakland only has 3 games left so they can't win 15), by splitting their remaining games as long as Oakland loses at least once (Wright State only has 3 games left so they can't win 14), or by going 1-3 if either Oakland loses at least 2 of 3 or Valpo beats Oakland. This covers 73.6% of all possible scenarios.
If both Valpo and Oakland finish 14-4 it means Oakland and Valpo split their season series and Wright State breaks the tie in favor of Oakland, due to Oakland's 2-0 record and Valpo's 0-2 record against this common opponent. Even if Milwaukee or Green Bay finish tied with Wright State, Oakland was 3-1 against these two teams. Even if Valpo sweeps both, it's not enough to make up for the influence of Wright State.
If both Valpo and Oakland finish in a tie for first at 13-3, the only way Valpo wins the tiebreaker is if they sweep Oakland.
Oakland can get the 1 seed by finishing 14-4 as long as Valpo loses at least 2 of their remaining games, since Oakland has all the tiebreakers if they split with Valpo. They can get the 1 see by finishing 13-5 as long as Valpo loses at least 3 of their remaining 4 games (Wright State can also finish 13-5, but obviously they get nowhere tying with Oakland). And as mentioned above, if all 4 teams tie at 12-6, Oakland wins the head-to-head-to-head-to-head tiebreaker. This covers 25% of all possible scenarios.
Wright State can get the 1 seed if they win out, Valpo goes 1-3 or 0-4, and Oakland goes 1-2 or 0-3. They will either win the regular season title outright or share the title only with Valpo, and in that case they obviously win the tiebreaker. This is the remaining 1.4% of the scenarios.