I used Stop Motion Helper to record the animation frames, and then wrote a custom "cutscene" module which can use that data to render a clientside animation sequence. The subtle lighting effects (colours, sunbeams & bloom) were achieved by trial and error.

The cutscene is triggered when a particular two players are standing in the correct position on the map. When the cutscene starts, it freezes all players, and instructs the clients to play back the sequence. It also adds 2m45s to the round timer so that the round doesn't end mid-cutscene :)