Criminal Sentence 229: Ambiguous or Ungrammatical?

From a newspaper:

"A backpack with a laptop and a vaccination card also was recovered."

At first glance, this sentence seems ungrammatical; it appears that the subject is a compound subject: "a backpack with a laptop and a vaccination card." Those are two things. So when we see the verb "was," we do a double take. Then we consider that the backpack could have contained two items: a laptop and a vaccination card. It's possible, so the "was" could be grammatical.

If the backpack really did contain two items, here's a clearer way to write this sentence:

"Also recovered was a backpack that contained both a laptop and a vaccination card."