Some context is missing here.
Prince of Egypt is playing David Geffin Hall at Lincoln Centre, which is being rented out like the Jeremy Jordan and Laura Benanti concert of Parade, the Ragtime concert with Lea Salonga and Norm Lewis, Titanic concert, Joseph with Noah Gavin, etc.
The Man of La Mancha concert is playing the Beaumount, but is a gala for Lincoln Centre Theatre. This is same as the Camelot concert with Lin Manuel Miranda, which somewhat lead to the revival a few years ago.
I believe too, Man of La Mancha has been swirling around as another show either Bart Sher wants to direct and/or in then category of older classic musicals that deserve another look at.