Actually, it turns out the speed limit at the spot of the pile up is 65mph in the general purpose lanes and 75mph in the tolled express lanes:
https://www.google.com/maps/@32.7875817,-97.3209603,3a,75y,3.19h,91.46t/data=!3m6!1e1!3m4!1sKadugkVsMocs9DnDT6sodg!2e0!7i16384!8i8192
But, yeah, add...