Should I go ahead and solder the pins on to the lcd and give it a try or should I try to return it because it may be faulty?
Yes you should solder the pins before you condemn the board. If it is faulty they should take it back anyway - how else could you determine if it works without connecting it to something.
connecting 5V to pin 15 and ground to pin 16 did make my text appear
Most if not all of the blue LCDs are illegible without powering the backlight so this is good advice. Since the backlight is rated at less than 5v you should probably use a series resistor in the line to pin 15.