Unfortunately most JWs do not stop and reason things out for themselves which is a shame as a simple online check indicates that the verbs are basically interchangeable.
TO DELAY
to put off to a later time;
defer (tr) to slow up, hinder, or cause to be late; detain (intr) to be irresolute or put off doing something; procrastinate (intr) to linger; dawdle
TO BE LATE
the act or an instance of delaying or being delayed
the interval between one event and another; lull; interlude Coming, occurring, or remaining after the correct, usual, or expected time; delayed: The bus is late. See Synonyms at tardy. Beginning after or continuing past the usual or expected hour: a late breakfast; a late meeting.
Occurring at an advanced hour
Conclusion: If something is delayed, it is flippin' LATE!!!!!!