There were no drawbacks for eating
zombie Puppet meat in SCUM. The caveat being that it had to be placed on a skewer for consummation and could not be cooked or consumed outright.
According to SCUM's Wikia page on Cooking:
"[Small Skewer with Meat] can be crafted with Puppet Meat and cooked with no ill ailments or side effects, for an easy source of protein early game."
However, as of patch 0.1.19.20050 from November 2nd, 2018 Puppets can no longer be chopped into meat or fat. If you somehow manage to acquire Puppet meat you should be able to consume it without repercussions, but it should now be impossible to get.