would there actually be any doggie doo left after being buried for 2 yrs ? id think it would actually make good fertilizer for said garden, but you would still have to remove the buried drum/container
Good point. The feces would be good fertilizer...and it would not be illegal to deliver their empty drum back to them. Its only delivering a drum with feces in it that would be illegal.
Using dog poop as fertilizer in a vegetable garden is a *ahem* very bad idea.
Dog poop can contain all sorts of nasty things which could contaminate the vegetables if it has not been composted at a high enough temperature. This includes, but is not limited to, retinal disease in children. It is unknown what temperature the dog poop container attained, but it has not been exposed to air, regular turning, or moisture monitored.
Disposing of your refuse on another party's property would be considered illegal dumping in many places, so it is best not to suggest OP do it.
I disagree with justalayman in that the issue was accepted as resolved by OP at purchase because the seller willfully deceived. If it's actually in writing that the poop drum was to have been removed, etc., as described by OP, and the seller signed off on it, then OP has an arguing point.