The cops told me even with the recorded image, even with their face, it's very difficult to find them unless if we recognise them

If you have a good facial image of him, post his pic on a community based Twitter feed and ask for help identifying him. Worked for a friend of mine. Plus, he deserves it.

which is why I'm considering installing DIY wireless security system from simplisafe.

I would have took desperate measures like notifying the pawn shops and other stores of the model of watches and other stolen goods to look out for in case they are stupid to unload them locally. That would get them on camera at least.