SUMIFS works fine with the following caveat:

I entered Times 8:00, 8:01, 8:02 in the first three cells in row one, 9:00, 9:01, 9:02 in the first three cells of row 3 and followed that pattern to the 14:00 row.
I then highlighted these three cells in those rows only. Then I drag-copied to the right to auto fill the rest of each hour's row.
I entered the formula SUMIFS(TTime,Exit3Ticks,"=" & 'cell directly above') in the cell below the :00 times and drag copied across to cover all times.
Some formulae calculated fine, some don't, However, if I type in the actual 8:40 in the failing 8:40 cell, the formula recalcs fine. If I re-drag-copy the time, the formula fails.

IsNumber returns True on all time cells and Named Range time cells.

The Spreadsheet contains no sensitive data but is over 4 mb.