That's certainly true. Kelli has played favorites for years. VK is hardly the first, and it's interesting to Jenna and Whitney lumped together as getting favorable treatment when I actually don't think their situations are all that similar. I don't think Whitney really got any punishment at all, whereas Jenna certainly did her last year.
With that said, I think Kelli tends to react differently when she feels personally offended. It seemed like her anger towards Jenna seemed oddly personal - not an employee screwing up, but someone not living up to her expectations after she made her a leader and favored her over the years. With Whitney, I almost think they chalked it up to her just being an idiot, so no personal offense. But that's also what sets the VK situation apart. Kelli set all of that up for her (Jinelle helping her/doctor's apput) and then she lied not just to Jinelle, but ultimately Kelli too. Anyone else would be on Kelli's shitlist for life. Kelli loves Meredith, but if Meredith got caught lying to Kelli, she would out in a heartbeat, and there would be no looking back. VK though didn't even really get dressed down. That was clearly due to their personal relationship.