Quartile/Average/Median In Array With Missing Data Points

Guys, I am absolutely desperate here...
The situation is the following: I need to use an Quartile formula for an array of numbers, meaning 2 data sets basically. First data set is a Group for each point there IS a value there (e.g. group ID) and nothing is missing. For the second (matching) data sets some points might be missing and in this case a lot of them are.
The problem: when I use an array formula on those data sets, it shows 0 for quartiles and median. And it shows "wrong" (low) value for average.

However, when I copy/paste the same data set separately and take quartiles/median/average and it DOES show values and not zero. So is there a way to make an array formula work (display results) the same way it works when I apply it to a data set separately?


The thing is that I absolutely MUST find a way to use it as an array, because my data structured in such a way (2 columns, 1 with 4 types of group id, and 1 with matching values - and I need to see quartiles/etc for them) and I can't change it much. I mean, I do understand that probably due to the fact that I'm using an array excel expects every matching point from data set 1 to have a matching entry in data set 2, but it's just not the case here. And I'm literally killing myself trying to find a way for array to "ignore" empty entries and work with what's available.

I would be forever thankful for any help on this, because I really am desperate here ((



P.S. You can find a sample file attached.