Thanks for flagging this, I will notify our PLM that this detail has been ommited from the T750 Data Sheet.
As a guide for now; I would use the R750 as a guide to the radio performance of the T750, as they share similar performance characteristics. This is stated as 31 SSIDs per AP.
The only 'gotcha' with this approach is roaming between zones isn't seamless, ideally the zones are in physically different locations or at least have some physical separation.