LFTB doesn't carry a higher risk of BSE or other prion diseases than normal ground beef. You're likely referring to concerns often levied at mechanically-separated meats, which is orthogonal to the product discussed here. LFTB is made from normal, boneless beef trimmings.
Don't worry, by the time people find out we gave them Mad Cow in 40-50 years, we can stack up all the extra profits in a Caribbean bank and be sipping margaritas with small grains of salt served by hula girls on a whole fleet of yachts.
BTW what is the average time CJD or BSE sets in humans?
Do you have a study to point at that would show some sort of timeframe?