From a pure logistical standpoint, shattering a knee cap, possibly the bottom of your femur or top of your tibia, and shreading all of the connective tissue in and around your knee sounds pretty fucking horrible.
The broadhead is going to slice the hell out of your hamstring and you risk a compartment syndrome and losing your leg entirely or the chance of bleeding out if it hits your femoral artery. Which are it's own risks.
Long term recovery is likely better for the hammy hit if you get medical attention soon enough.