Translation:Have you all read the email?
Although literally different, it should be accepted.
Personally I never say 你 查看/检查/更新了电子邮件吗？. I only do so when writing.
I still get a bit confused with the positioning of 了.
Is the following also acceptable: 你们看电子邮件了吗?
I've heard that most people in China will recognize the word "email", is this true?
Maybe, but even if they recognize it, you won't hear this English word from many people. In everyday conversation, the most common word for email is 邮件, which is easier to pronounce and to type than 电子邮件 and email.
I believe most countries in the world just say "email" nowadays, it's one of those words that have become a globalized term.