Get one of these. I have had mine for 4 years now and it works great. Not one false alarm. If it goes off at 2AM something's up. It has woken me up twice now to door checkers. If you use an Energizer Lithium 9 volt it will last a full year.
Interesting video. He proofs to "know" how to dismantle the first cam, however he "forgot" to completely disable the second set? The unplugged UTP cable intriges me: was that from another cam/floodlight/ir beamer?
In any case, if I was you, I'd grab a couple of additional cams, or, if wiring is a challenge, you could throw in a couple of dummy cams in the corner of your garden. Don't take the ones with these flashy red leds, but some light glowing "fake" IR leds. And add some motion trigggered flood lights. Not only your intruders can be "flashed" and "surprised", your footage might be better too (except if you aim the beam into a cam). And last but not least: if the border/gate contains a mailbox, you can hide a cam in it facing your house, so when the intruder jumps into his car, he might take off his disguise, and you might have a better view.
I have a BI system with 9 cameras around the exterior of our house and the driveway. I started off with 3 cameras and gradually increased and improved the system over the last 5 years. By far the most important thing I learned (as the result of an actual theft from our garage) is that although most of the cameras recorded the thieves at some point, it was the two that I happened to have mounted less than 6ft from the ground that recorded really good mugshots and led to the police arresting them some time later. Ok they are vulnerable to being damaged or stolen (although I had mine well concealed so the thieves had no idea they were being filmed) but the cameras that were mounted high up out of harm's way only showed the tops of their heads. I've since moved most of them to much lower positions.