Majority of Marners points came in games 1 and 2, he was pretty bad the rest of the way. Rielly, O'Reilly, Schenn and Matthews were great in that series, Nylander and Tavares were good, Marner was good in the first 2 games, mediocre the rest of the way.
With all due respect I think you're too caught up in stat watching, because if you watched the series and remember it, you would know how many garbage time points Marner got in that series, I think he 7 points in the first 2 games if I'm not mistaken.