When facing stronger teams Gladbach tends to play inconsistently. they sometimes play well when playing against teams that are equal to, or worse than them. but facing Dortmund, Gladbach can probably only pray that Dortmund will play badly and that's the chance for Gladbach to get a win or at least a draw. like when they held Freiburg to a 3-3 draw.
In terms of opportunities, Dortmund is certainly more favored. but we don't know Dortmund's readiness to face this match.
So far with all the performance Dortmund has had in recent times, I don't think they would want to loose this match against gladbach for any reason, because they at this point definitely want to makeup for their poor performance recently so any opportunities with any team that seem Weaker than they are will be utilized.
Gladbach would only hope to get a draw but sadly they are away so it really going to be tough because Dortmund would not give a chance not at home to a team they consider a little weak than they are, hopefully the win margin may be small if Dortmund eventually secures three points playing against gladbach but if it turns out a draw then it will be considered a good match for gladbach because Dortmund is above them in almost every stats.