And remember, the poster indicated the panel was sans Fox because Fox was left out.
Seems, rightly or wrongly, the left themselves out.
Actually, it was untrue that C-Span invited Fox and they declined. The talking-heads present were invited by Harvard University. No mention was made at the end of the show if Fox was invited or not. I'm not convinced they were. Perhaps someone else heard that they were, but not mentioning that Harvard set up the program makes me suspect that report.