Yes, I had no idea it was the four extremely small Philips screws on the 70-200 lens foot plate itself. I guess all the usage loosened them.
I was able to secure them a little more using a small flat jewelers screwdriver, although it wasn't a Philips head nor the ideal size and I certainly didn't want to strip the screw heads.
So I just ordered myself some camera repair-quality precision Philips screwdrivers from www.micro-tools.com in sizes 000 through #1. Should come in handy for better securing this lens plate and some of my other camera gear with those tiny micro-sized screws. And come to think of it, I had trouble opening the battery screw on my Phottix wireless remote too.