Summing wildcard matches while subtracting wildcard matches of the previous rows

Hello and thanks in advance for the help!

I have a column of cells each consisting of a list of substrings separated by a comma. next to this column is another column with numerical values. Example:

A | B
a,b | 3
a,d | 15
c,d,b | 2
a,b,c | 8
c,a | 6
d | 9
b | 11
a | 4
a | 2
c,a,b | 1
a,d | 7
b,c | 4
c,d | 6


The substrings in col A are ranked:
1 a
2 b
3 c
4 d

Now, i need to sum column B for each of the 4 substrings, but making sure not to count the cells where it appeared alongside a higher ranked substring. I already have a formula that counts the instances of each substring when not appearing with a higher ranked substring (column E in example file) using this formula: {=SUM(N(MMULT(1-ISERR(FIND(TRANSPOSE(D$1:D2),A$1:A$13)),2^ROW(D$1:D2))=2^ROWS(D$1:D2)))}. In column F of the example file, I show what the results would look like for what I'm looking for.

Would appreciate some help on how to solve this.

Example spreadsheet attached

Thanks

If you have the filter function how about
=SUM(FILTER($B$1:$B$13,N(MMULT(1-ISERR(FIND(TRANSPOSE(D$1:D2),A$1:A$13)),2^ROW(D$1:D2))=2^ROWS(D$1:D2))))

That works, thank you very much!

You're welcome & thanks for the feedback.