Cool. Just wanted some clarity. Looking forward to the results!
This is fairly basic stuff.
All "vital" goals are not equal. "Winning" goals is nothing important, it's just to classify some goals as the final goals that separated the game. A 2-0 goal doesn't qualify for example, since the winning goal would have been the 1-0. With Lukaku I think all of his winning goals were PKs.
As I said earlier, if I were to do this more professionally, I'd assign several metrics and do case-by-case evaluations. For example, several of Lukaku's 'vital' goals came at the dying minutes of a game we were leading, but since this is standardized everything is equal. Making it 3-1 on the 90th minute when the opposition appears to have given up should not be the same as making it 2-0 at the beginning of the second half, killing any momentum the opposition would have going etc.
Also, "low effect" goals include goals scored after a 2 goal lead or goals scored to reduce the deficit up to 2 goals. So in a 1-4 situation where the score becomes 2-4, it's still a low effect goal. There was a case with Kane vs Bayern iirc there which this applied. It also applied with Immobil in a situation where Lazio went from 0-3 to 3-3. Clearly that goal was more valuable than Kane's after all, since it enabled a comeback that gained Lazio a point. But once again, this is standardized so it's not going to be seen there.
Oh, and Lewandowski and Bayern score a shitload of goals and have large margins, so it's rather awkward to compare him with everyone else

He's had as many 'low impact' goals as others have scored in an entire season, reminds me of Cristiano at Real Madrid, whose stats should look similar.
P.S: I couldn't be bothered to add both 'vital' and 'winning' goals together, so you can just see the low effect% or add them together if you don't like the one that excludes already included PKs.