is it true that in a 2012 versa there is a reset button for the blower in relation to a dirty in cab filter?

No.

is there a relay on the blower motor that can be replaced?

Its not on the motor, but yes.
What is your concern?

my blower stopped working, changed out climate cluster control, thinking it was the switch. got power to motor but still will not work. trying to figure out if i have to replace blower? if i can find the relay maybe i could test it, first.

If you have power at the fan motor, then your relay is OK.
For reference, the relay is at the left side of the fuse block.
Check both of the 15A fuses for the blower anyway if you haven't already.

If you ground the other terminal at the motor, will the fan operate?
I know its kind of up in there, and no so easy to get to.
If it won't run, the fan motor is faulty.
If it does, you need to take a look at the ground coming from the front air control (fan switch)
Look at the ESM here: http://www.nicoclub.com/FSM/Versa/2012/Hatch/MTC.pdf
Pages MTC-27, and MTC-35 to 38.

i took the plug out of the climate cluster control and jumped to ground from the plug and was able to get the 4 speeds to run the blower. since this isolates the fan switch would this be conclusive enough to say that the switch is at fault and must be replaced? that is the first thing i did. i replaced it with a used one i got on line. could both be bad? the original and the used one?