Most of the drivers have a combination of CC and CV control on the output. Meaning they will increase the output voltage until the maximum set current is reached through the load, or the max set voltage is reached.
Connecting a 700mA constant current driver to a single panel would be a very bad idea. The linked driver could potentially output up to 142V, so it will raise the output voltage until it pushes 700mA through the single panel, probably destroying it in seconds. Adding a resistance isn't a solution since the driver will try to increase the output voltage to try and reach the 700mA target, it will only limited once it reaches the 142V max output voltage. But now the resistor will be dropping around 22V at 0.7A which gives you 15W dissipation in the resistor.
When you use a CC driver on 2 panels in parallel, the 700mA will be shared between the 2 panels, but the exact ratio is a little tricky since LEDs are non linear and the forward voltage lowers with an increase in temperature. Adding a small amount of resistance to each helps to match the ratio of currents, without dissipating too much power in the resistors. There is the potential to destroy a light if one goes open circuit, the full 700mA will be forced through the other light, destroying it. This is where an additional CV adjustment pot is ideal since you can set the max voltage to just above the voltage needed for CC operation. Alas the linked driver doesn't have it, only lower voltage ones do in the 24-54V range.
The driver could potentially work on a single panel if the dimming control was set to around 35% of its 1A output capability, but if you look at the datasheet, that is slightly outside the recommended I/V operating area. You'd need to ensure it starts in a failsafe way, ie the dimming control always works when the driver is on (like a simple potentiometer)
A 350mA driver for each panel would be ideal, but you need to find one that is capable of outputting up to 120V. I didn't see any suitable options, though something might be out there. Also even if you find something within those specs, they might have higher ripple anyways, bringing you back to square one.
You don't stand to lose much by buying a single test unit