Not part of the team but I think I can still answer this.
This is most probably not possible. The reason is simple: The dialogues are timed. So every bit of it is played at a specific time. The time acceleration won't affect the way the dialogue sounds, but it will affect the timing. If you normally have 4 seconds between two parts, at 4x time acceleration you only have 1 second, at 64x there are no pauses at all anymore. This could probably be fixed by using 64x the pausing times, but who knows if the part will be played when flying at 64x or if the autopilot has already slowed to 16x acceleration.
And.. nobody forces you do use the autopilot alltogether. The mission goal wants you to activate it, but nobody keeps you from deactivating it a little earlier that it would automatically.
So it is really hard to impossible to determine what time acceleration the player is using at that moment, so puting dialogue in a potentially time accelerated place of the mission is a big problem, although I agree that those conversations would fit in there best. Maybe the developers can come of with something to improve the way the autopilot works. Then one might be able to put the dialogue sequences there.
