But you are completely overlooking the commercial markets. Commercial buyers such supermarkets, restaurant chains, public sector will not run the risk of putting game products into the market when they contain lead. The few that do will put warning label about the risks of lead on the packet.
So Mrs Housewife who has read about, or seen on Masterchef venison being cooked. Following day in the supermarket she sees and picks up some venison steaks - all healthy, good nutritious meat according to everything she has read and heard. Then she reads the warning label about the dangers of lead and potential harm to children.
Puts packet of venison back on shelf and picks up some intensively reared pork or chicken product instead.
One potential customer and advocate for shooting wild game lost.
The venison industry has been shooting itself its own foot for last upteen years. Lead used to be commonly used to solder cans of meat and fish closed. This was prohibited over 60 years ago. Yet we still think its perfect OK to contaminate a beautiful free range meat product with one of the most harmful metals known to man.
Have a read of the proceedings in Parliament from 1961 on lead in every day foodstuffs. Linked below.
In those days if you survived more than a year or two after retirement at 65 you were considered to have done well. Now we expect to live into our 80’s.