Looks like a stressed Gar or one that was kept in a tank with a very light background and substrate in my opinion. I had a Shortnose that had absolutely no color when he arrived(ghost white) and within a week or so of settling in he took on his regular colors and patterns.
There are different grades of platinum gar. The less spots on the body and tail, the better the grade. Since you might have paid quite a sum of money for the platinum gar, try to get it from a reliable dealer with an assurance that if it does not stay as white as you got it in one to two week, you can return it. The first and last pictures makes it a bit questionable that it is a platinum gar.