Take the the bag and stay schtum.
Say owt to your insurer,and your premium on renewal will increase as you have a declared accident,on your record,even tho no payout has occurred.
And before the hang-em high, brigade start up,,report a non payout accident to your insurers and see.
What he said, unfortunately.^
Had the same situation myself once. My insurer said the 3rd parties lack of insurance was "no problem" as I'm comprehensively insured. No problem except for my excess, of course! They were, of course, "unable to trace" the 3rd party. I wrote to the 3rd party and asked politely for my excess, and received a cheque by return of post. Thought I'd better go to the Police and report this uninsured driver "Oh, you'll just be needing an incident number from us, then?".

That plus the fact that your Omega will be written off if it goes anywhere near an insurance claim. Just take the money and advise the guy to get insurance before it's someone's kid in his path. It's not the "right thing" to do, but, in this instance, doing the right thing will just cost you money and aggro.
