It is practical to hand solder the RedPine’s wifi module to a Current Cobra II? I see on Amazon that a purchasing them soldered together cost 2x what it costs to boards themselves?
Yes you can, soldering experience is needed though.
It’s not too difficult as the connections are spaced out but as Gus said, if you have soldering experience to start with it will make it easier.
One thing I would recommend is to get yourself some no clean tacky flux and use this on the PCB pads before placing the module. This stuff works wonders when trying to solder this type of device. I was a recent convert to this stuff after using flux pens for years. I wish I had discovered it all those years ago! 
+1 on tacky flux…
Tacky flux uh… I’ll look into it.
There appears to be a pad at the bottom of the module and I was hoping to not have to solder that.
It is only the outside connections around the perimeter of the board that needs soldering?
the bottom path is a gnd, but you have multiple on the sides to.
Works fine without soldering the center one.