my commanders randomly exploded soon after I took middle. I think that was a bug, I didn't see any enemy units in the replay.

It's partly a bug, partly your own fault. You jumped two commanders onto the same spot, around that spot were solars and other buildings. When landing your two commanders pushed each other (because that's how Spring phsyics work), apparently dealt and received collision damage from the nearby solar and one another, maybe also the mex that was under construction.

For anybody watching the replay: the incident happened around 8 minutes and 10 seconds into the game on the southwestern "wing" of the central hill.

I don't think that was it skasi. I've had that happen before in single player with only one commander and the buildings weren't that crowded. That time it was near the edge of the map, but this time it was right in the middle.

edit: although it plausibly could have been a 'squish' issue. That's kind of obnoxious.

Also, I ended the game with control+d, I didn't even have my commanders selected when that happened. They were just following global build. :P

that time it was on titan duel, I don't think there are any rocks. He just happened to jump near the edge of the map. I think there was a mex there, maybe a solar, but they weren't all that crowded. There weren't any other units nearby that time either, just 1 com.