Mini solar panel not working
How about trying something a bit different to make things easier.
First, let's see if you can light up an LED with using the solar panel.

Build the following circuit.  







simulate this circuit &ndash; Schematic created using CircuitLab

Calculating Resistor Value

I calculated the resistor with the following formulas.

6V - 2V (approx drop for LED) = 4V

We have approx 4V to use to calculate the current.
Current for the resistor can be about 20mA

4V / .020 = 200 (Ohms)

Does the LED light up?

If the LED doesn't light up then we are misunderstanding how the solar panel is providing current.  And I think that is part of the problem.
This may help you get to your answer.

Next thing you can do is insert your ammeter and see what current you may be getting.

Alter the previous circuit by adding the ammeter (multimeter in amp reading mode) inline:







simulate this circuit