Could you help me with the following phrase I came across in the newspaper?

I have trouble with the last phrase, "No telling, then and now." What does it mean?

This striking tidbit of history is well-known among legal scholars, but not the general public. Embarrassing? No telling, then and now.

Apple

I've found the full citation, which is about an event years ago that could be or could have been embarrassing for those who took part in it.* The single utterance "Embarrassing?" is a reduced question, which would be, in its full form,

"” Is/was that act embarrassing for [those who did it]?

The answer "no telling" is also a reduced sentence. Its full form would be

"” There's no telling ("no way to tell/know") whether it is/was

"For then and now" is not clear to me. It's some kind of comment on the previous statement, as if it had ended with a comma instead of a period. I think it means "There's no way to tell either whether it was embarrassing then or whether it is embarrassing now."

Marilyn

*The version I write here is slightly different from what Apple has written. I have reproduced it as it appears on the Web.