Indeed this looks similar like an old bug from the SC2000's characteristic.
It was worse when only the mission
host could destroy
all ground targets with the SC2000,
clients would bomb with only a
single target being destroyed, all building were destroyed as expected with this demolition type bomb.
This wasn't changed for a long time as it only affected CooP missions and not Dogfight servers, I reported the bug for over a year to Oleg & co iirc.
I hope its not returned in v4.11
