Advice before I do this..

Yesterday at work a colleague reversed into my car. I didn't see it happen but I saw him get out of his car and check the back of both cars. He then came in and went back outside with another colleague and he looked at the back of both cars. I can see this from my office window - they obviously did not think I could see. I was furiously waiting for an explanation. They came back in and the one responsible for hitting my car 'thanked' the other one and they both got on with their day. I was so angry. I've bumped into somebody else's car in the past before, and even with no mark, I'd still tell and apologise to the owner. 

As the day went on the likelihood of an explanation and/or an apology decreased and so did my confidence - did he really hit my car then? Self-doubt started creeping in and I couldn't go out to my car to check because I didn't want to bring unnecessary attention to the situation. So at the end of the day I was last out and could check my bumper. The dirt on the back had been smudged by fingers and there were fresh cracks in the paint work. He HAD hit my car. It played on my mind all night.

This morning am I going to check cctv but I don't have access to it - I'll have to ask another colleague to show me it on their computer. It's an open plan office so it'll be obvious as to what I'm looking for. When I see the evidence what do I do? The situation is made worse by the fact my bumper is already cracked so badly underneath that I wouldn't get it repaired anyway - it probably needs replacing. (My car is bright yellow and I've never owned a car that's been hit by so many other people. 2 have gone into the back of me previously and I've already had it repaired! It's yellow! How can you not see me??).

I am 99% sure, even with evidence, he'll lie about it and I'll be forced into a public confrontation. I hate dishonesty. If he'd have told me yesterday I'd have thanked him for telling me and told him not to worry.

I don't need this on top of my already stressful job. I am correct to pursue this aren't I?