When I export the Drill file with Drill export options: Zero Suppression set to Trailing, I get a Drill file shows Suppression format as leading:
Shouldn't it be the opposite TZ?
There may be a bit of clarification with the Zero Suppression.
When Trailing is selected it means to eliminate (i.e. Suppress) the zeros that Trail -- thus the leading Zeros remain. When you select "Leading" than the Leading zeros are removed and the trailing zeros remain (if any).
Note: In the example above, FAB 3000 correctly outputs with Leading Zeros (LZ) because you have instructed it to Suppress Trailing Zeros on Export. Thus a drill coordinate X007500Y007500 will appear as X0075Y0075 which means the trailing zeros has been suppressed as instructed.