In the book, Pendalfe did not ask for eagle support at all. The eagles themselves walked in the vicinity, noticed a loud hustle and decided to smash the goblons, to which they fed racial hatred.

In general, it was emphasized in every way that eagles, first of all, are in their minds and even piss the sheep, and secondly, not all eagles are equally useful, so that it is not quite safe to trust them a secret operation.

Although he was originally a debtor to Pendalph, he clearly indicated the limits of his gratitude. For example, he refused to drag the knot into places with the presence of humans and as a result of the developed air defense system (on the latter, Smaug will not lie)