I would never rely on online pics. Yeah, they're could be intentional manipulation like pumping up the saturation and so on, but they're could also be unintentional conditions that would cause the coral to look different to you on arrival.
For starters, is your monitor color calibrated with the vendor's monitor and with the camera? I'm going to go out on a limb and say probably not, and that the difference could be very profound. I took some pictures at a car show once and shared them online, and then a guy commented on them that the pictures where very nice but that I’d gotten the color wrong on several of the cars. My gear and monitors where all calibrated and I was pretty sure his probably weren’t. Most people don’t realize how big the differences can be which can be a challenge when selling or proofing online with a customer.