There is a DART BUS station across the street from him. According to the bus route. catch the 409 at 7:09 ON OAK Lawn where it meets Cedar Springs. that gets you there at 7:40am.
But it's gonna dump you on the by the MLK station on the SW side of Fair Park...
If you want to walk a mile over to Market Center station. you can catch the Green line at 7:32 and get off at fair park station at 8:01. UNKNOWN AS if you catch a green line south.. it's NOT going to FAIR Park station on saturday.
https://www.dart.org/rideralerts/fullra.asp?id=4627
* Green Line trains operating south from Carrollton to Buckner will bypass Victory Station and continue to EBJ Union Station, then proceed non-stop to MLK, Jr. Station
* Green Line stations missed by this detour - West End, Akard, St. Paul, Pearl/Arts District, Deep Ellum, Baylor and Fair Park - will be served by special "Fair Park" trains operating east from EBJ Union Station.
*TRE passengers will transfer at Victory Station to shuttle buses to complete their trip to the fairgrounds.
I strongly suggest you download and install the GoPass app as it will typically show the realtime delay of trains ..but i've never tried it on this area on this weekend.
*EDIT* updated