Assuming your columns start from A:A (thus Cause is E:E and Total is
F:F). Further assuming that you have 100 rows, thus your table data are
in A2:H101:

Highest total for a given cause:
=MAX($F$2:$F$101*IF($E$2:$E$101="MyCause", 1, 0))
To be array entered (Shift+Ctrl+Enter)

Suppose the total is in cell K2. Then, to find the customer with this
total,
=INDEX($C$2:$C$101,MATCH(K2,$F$2:$F$101,0))

HTH
Kostis Vezerides