How to finish retaining wall for a paver patio on a sloping ground?
If you can't add a coarse of block from the step out to the end, so that the top of the entire block wall is all the same, then I would consider removing the blocks from the step out and excavating to lower them down so that you can.

To accomplish water runoff you can: 


build the retaining wall perfectly level then hump the patio pavers higher by
an inch or two about 2/3 of the way down the middle from the house out,
pitch the entire retaining wall in a direction as if it were one
monolithic thing
or a combination of the two.