These are in NTIRN. There could be a few others that have not been verified. I don't see anything specific to the Winspear facility.
Dallas Office of Cultural Affairs
33251 81e3 T Dal Maj FOH Majestic Front of House
33252 81e4 T Dal Maj Stage Majestic Stage
33253 81e5 T Dal Maj Security Majestic Security
33254 81e6 T Dal Moody FOH Moody Performance Hall Front of House
33255 81e7 T Dal Moody Stage Moody Performance Hall Stage
33256 81e8 T Dal Moody Securi Moody Performance Hall Security
33257 81e9 T Dal Lat Cult Ops Latin Cultural Center Ops
33258 81ea T Dal Lat Cult Stg Latin Cultural Center Stage
33259 81eb T Dal S Dallas CC South Dallas Cultural Center
33260 81ec T Dal BathHouse CC Bath House Cultural Center
33261 81ed T Dal Oak Cliff CC Oak Cliff Cultural Center
33262 81ee T Dal OCA Maint Maintenance
33263 81ef T Dal OCA Pub Art Public Art
33264 81f0 T Dal OCA Ev A Event A
33265 81f1 T Dal OCA Ev 2 Event 2
They might not be using NTIRN. I found this license with a number of DMR mode frequencies:
FCC Callsign WQJY847 (AT&T Performing Arts Center)
www.radioreference.com
When I get a chance, I'll set up a "dummy" system to see if I can hear anything from my location in Oak Cliff.