Index Match in Alphabetical Order with Criteria

I would like to have an index match function provide a unique list of items in alphabetical order and at one criteria for now.

=INDEX($C$2:$C$52,MATCH(0,COUNTIF($C$2:$C$52,"<"&$C$2:$C$52)-SUM(COUNTIF($C$2:$C$52,"="&G$1:G1))+IF($A$2:$A$52<>"AI",1,0),0))

But I think what is messing up this is the criteria part that shows +IF($A$2:$A$52<>"AI",1,0). Without this, I get the entire list, sorted into alphabetical order.

When looking at the attached spreadsheet, I'd like to filter out only if column A includes "AI" and then uniquely sort this in alphabetical order.