Will D.Va's ultimate damage players on her team?
Solution 1:
No, D.Va's ultimate will not damage her teammates.
In general, no abilities can deal damage to teammates. The only direct way to kill a teammate is to do something that pushes them of the map.
If you see the 'TEAM KILL' notification in the center of your screen, that is actually to denote that your team has wiped the enemy team, not that you've killed a teammate.
In the case of Reinhardt's shield, it can block any damage (except for Symmetra's moves, Winston's gun, Junkrat's Rip Tire, his own Fire Strike ability, and Hanzo's Spirit Dragon) as long as it has at least 1HP. So a 1HP Reinhardt Shield can take the full 1000 Damage of D.Va's explosion.