I purchased the car about a year and a half ago and I have put about 4k miles on it. Haven't ever even opened the coolant resivoir up until the other day when I added coolant. I did bring it in to get the brake switch looked at and get an oil change so I don't see why they would have messed with the cooling system but it was a dealership so who knows .
For now it's fixed, if the problem arises again then there must be more to it. Here's to hoping there isn't