Aflatoxins are produced by fungi that grow on grains. (Toxic stuff that is naturally occuring.) Think liver damage at high levels and cancer at low levels over the long term. Toxic levels are measured in parts per billion.

Grain that is used for human consumption is tested for aflatoxins. A few parts per billion will condem grain for human consumption. I do not know the levels right off, but FDA has standards on what is acceptable.

Livestock feeds are also regulated since they go into food animals. A higher level of aflatoxin is acceptable for livestock feeds. Depends on the animal. Dairy cattle feed is one of the more strictly regulated, since aflatoxins affect milk.

Deer corn? Deer corn does not have to meet human food standards. Depending on your state regulations, it probably does not even have to meet livestock standards since deer are not a food animal. By that I mean they are not subject to inspection and the meat is not sold commercially. They are not regulated by FDA or USDA.

I do not know the state regulations where you live, but "Deer Corn" probably does not have to meet any standards as long as it is corn.
I am sure it would not have to meet human standards. It could be bagged from the same supply as livestock feeds or it could be corn that has been rejected for livestock feeds.

To make a long answer short: I would not eat it. The quality could be excellent, but you just do not know.