Most Recent Values by Date with Index and Match

That's is because you're using exact match on the dates, so any tie will always return the first matching entry.

With a single formula,

Formula:

=INDEX($B:$B,AGGREGATE(15,6,ROW($A$2:$A$21)/($A$2:$A$21=LARGE($A$2:$A$21,ROWS(E$2:E2))),ROWS(E$2:E2)-COUNTIF($A$2:$A$21,">"&LARGE($A$2:$A$21,ROWS(E$2:E2)))))

it can probably be simplified with a helper column.

edit:-

With a 2 column approach

In D2, fill down 10 rows

Formula:

=LARGE($A$2:$A$21,ROWS(D$2:D2))

Then in E2, fill down 10 rows

Formula:

=INDEX($B:$B,AGGREGATE(15,6,ROW($A$2:$A$21)/($A$2:$A$21=D2),COUNTIF(D$2:D2,D2)))

I was thinking of a pivot table, but I'm not sure that you would be able to get the results in the format that you want.