Rav Hirsch explains Ki Sisa 32:24 as meaning that Aharon did not try to explain all the details of the event and that he had tried to delay the Jewish people unsuccessfully. He glosses over his attempts to prolong the actual work and tries to skip over the murder of Chur and his own danger had he completely refused.
How great Aharon show himself in this reply! Not a word to justify
himself, does not mention the circumstances of which we know, which
would serve to modify his guilt. Nothing of the overwhelming
threatening mob - וַיִּקָּהֵל הָעָם עַל אַהֲרֹן - nothing of his
attempts to use the vanity of the women as a means of delay - nothing
of his laborious work of engraving and modeling to postpone the
completion of the work as long as possible - nothing of all this. He
will not adduce any reason for the mitigation of his own guilt which
would increase the guilt of the people. He takes practically the whole
guilt on his own shoulders, accuses himself of the most listless
weakness.