I think that mount is for solid siding (wood or fiber cement). For vinyl, you need something with j-channel. Something like this one:
http://www.lowes.com/pd/Severe-Weather-7-5-in-x-7-75-in-White-Vinyl-Universal-Mounting-Block/3034223
You have to cut a big hole in the siding, through. The one in the link above would require a hole the listed dimension (7.5 x 7.75 inches), in which the j-channel backer is placed. Once done you can put the camera's j-box or whatever inside the backer and then place the cover piece (after cutting a hole in the cover piece to accommodate the junction box). This kind of mounting block is necessary to keep water from getting behind your siding. If you just screw a block onto the siding, the screw holes and compression of the siding by the mounted item will likely cause water infiltration. I have not used one specifically for a camera install yet, but I used them for light fixtures and similar items for dryer, oven, bathroom, etc exhaust vents.
I've also seen folks make a custom mounting block using a solid block (exterior-grade wood, miratec, or something similar) with j-channel around it, which looks better if done right as you can make it the exact dimensions you need.
The above is based on experience mounting non-camera items, so perhaps a pro can chime in with how they do it.