Extras in your print book! Use the frames from the animation however you need to in print form, maybe using one or two keyframes as panels, whatever, in the actual comic. Just as the panels in any comic are simply key seconds in an actual action or event.
But then, have a section in the back of your print comic that shows the animation process including more or all of your frames! You could put whatever you want in these Extras pages: any sketches or storyboards you did, a little tutorial on making GIFS, the sky is the limit.
But it's always a great idea to have extra content in your print comic, to encourage the purchase of something which was already offered free online. Showing your animation process would be a great Extra!