Hi:
May be something like this (after removing the duplicate record without metadata, your bullet point 2.)
=IF(AND(COUNTIFS($A$2:$A$3,A2,$B$2:$B$3,B2,$C$2:$C$3,C2)>1,D2=""),"Delete","Do Not Delete")
and filter for "Delete" Flag to remove the record without metadata.
Thanks