I'm guessing it's some technicality... the Strzok type is known for this type of hair splitting... he WAS subpoenaed but not for this particular 'time' or some such 'exception' and in his mind negate this essence of the question. He's a horrible person. But your right - I hope it comes up again... it's shows him for the type he is...
Turning red again on wording for Clinton investigation. Strzok made the change on his computer.