Nowadays, insurers ask that no liability is ever admitted by the roadside - let the companies earn their cash and sort it out on your behalf.
Obviously, your incident was minor and you were stationary, so it would be pointless for him not to accept all liability.
If he, or his insurer, directly contacts you again, I would refer him/them to your insurer.
Words of warning though:-
a) Get in touch with your insurer asap to get them up to speed, I know you were busy, but nearly 4 days to report an (albeit minor) accident is a long time.
b) Check if there is a potential excess to pay on your policy, and
c) If you DO have to pay an excess up front, will you get it back since you are 0% to blame.