the short answer is "no"
you admitted whatever it was - when you accepted the caution
and so the opportunities for pleading later " I didnt really" are limited or else cases would go on and on [more than they already do]
If you want the property back you should go thro the "proper channels"
write a letter, write a final letter and then go thro the small claims court.
You cant just say "he owes me money" you will be required to prove it
Recovering property or a debt thro the courts when you have admitted harassment or in my case got a PIN ( basically it is a warning - I didnt accept the PIN I got it ) is a bit of a run around but it can be done - [since I er did it]