I've also been thinking for quite some time about this quest. If you steal the acclaimed werewolf blood only, that is nearly as supicious as if they really got a chance to examine it. So I'd say no violation for being seen unless you are a Nossie or use overt disciplines. But no redemption either.
Calling the police on the other hand sounds quite logical.
My idea was to put a bag of real wolf-blood in the mailbox when you get the quest and ask the pc to make a swap without being detected, or if you can't pull that off due to lack in sneaking or hacking for turning off the camera make it look like a raid and also take the things from the medical store next door.
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