It also just occurred to me that there is no mention of a suspective motive in the report

    The police statement did not provide any details on the circumstances of the stabbing.

    “This is an open and active investigation. For that reason we are not releasing further information,” Officer Niccole Pacchetti, a public information officer, said in an email. “We will provide further details when they become available.”

If it was an obvious robbery, I would expect the police to be OK with mentioning that in their statement (in other words, saying valuables were taken and it looks like a somewhat random robbery).

And maybe his wallet/phone were taken, but if police thought it was an open-and-shut motive, I don't see why they wouldn't mention that.