GETPIVOTDATA possible with X & Y axis having Subtotals?

I can't post the actual file and there are too many lines to recreate something simple so a yes/no answer will work if that's all I can get.
I have setup a pivot from a data dump of about 60k lines that is updated monthly and the data source of the table is a named range.

My issue is I need to get only the subtotal number on the bottom right of the table. I can make the numbers for each deficiency above the total show up but get a #ref when I select "grand total" as the reference row.

The table is filtered to top 10 of maybe 60 total deficiencies. they are filtered in order largest to smallest and the layout is in a tabular form so the severity level is on its own column.
The amount of columns will never change but the rows could. (show items with no data is selected but rows could have more than one deficiency type per new metric level)

is GETPIVOTDATA appropriate or possible here for the bottom right GRAND TOTAL or should I use OFFSET to get the number which is linked to another worksheet?

Thank you in advance for your help!

This is the formula I have that pulls the result for each deficiency.

=GETPIVOTDATA("Severity Level",$AK$9,"Metric Level3","(Blank)")

it only does the Grand total column though. If needed, how do I pull the deficiency by shop? say I wanted it to pull the same row but column "51" ?

thank you!!!