If I understand correctly, you are not sure that one or more of your co-workers saw the the screenshot, and if any did, they didn’t see it for long because you deleted it immediately. Whomever saw the screenshot for a few seconds, can’t remember the details well, I imagine, because it was removed very quickly. As people live on, having new visuals, old visuals become even more vague, until those visuals are nothing really.
If anyone mentions the screenshot to you, say something like: it is embarrassing to me that it happened, I regret that it did, let this be a lesson to us all (to avoid the specific technical mistake that led to the sending of the screenshot).
I am sorry to read that the screenshot was forwarded. Well, that was done and it cannot be undone. Hopefully, soon enough, this screenshot will be old news for anyone and everyone who has seen it, and it will fade away from people’s memories. New events in people’s lives, new interests, new concerns take the place of old news.