Conditional statement query

Hi guys,

I came across the following conditional statement when reading a newspaper.

President Vladimir Putin, himself a former KGB spy, said earlier this month that Skripal would have been dead if he was attacked with a weapons grade agent.

I learned, for if statements, we use the combination of had + would have, for instance, if I had gone to the university, I would have gotten a high paid job. Therefore, shouldn't the word "had" was written in the article instead of the word "was"?

President Vladimir Putin, himself a former KGB spy, said earlier this month that Skripal would have been dead if he was had attacked with a weapons grade agent.

Thanks

Faraz Amjad