Tense of "Beause of"

Please look at this question.

"Because of a lengthy discussion Mr.Klose________with the vice president, he was thirty minutes late to the annual awards ceremony."

A) had
B) has

The correct answer is B) has. I thought its correct answer was A) had. "Since he had a discussion with vice president, he was late. "
Is my thought wrong ? Please explain to me why it should be B) has ,and tell me whether or not putting "Due to" instead of "Because of ' in the sentence.

Thanks in advance.