Let's go about this bit by bit. First, your if condition:

If(ROWS($G$6:G6)<COUNTA($B$6:$B$21)

If I'm reading this right, if the row number in the right table is less than the number of entries in the left table (in this example, 4), right? That being it should return a blank (the true result) for the first three rows. Only once the row number equals 4, thus equalling the count, will your formula (the false result) be calculated.

Is that right or is it backward? I would think you would only want it for the first four rows i.e. >=.

Assuming that, it lookslike COUNTA is not going to work since it will count cells with formulas regardless if they return a result. So I tried this:

=IF(ROWS($G$6:G6)>=ROWS($B$6:$B$21)-COUNTBLANK($B$6:$B$21) ...

I tried that and it get's the first and the third names, but misses the other two.

Progress? Um, maybe.