He can sit. Sitting is good. Optimus's vents cycle one final time as he eases himself down, not-quite-hunched over but close. This is about as safe as he'll be; there's no point in him stressing, because if he's chosen poorly...

He'll know soon enough. (He can't not keep the thought in his processor, however small and poisonous it remains. He wants to be able to feel safe, but when enemies are coming from those he thought were friends...)

"Clearing out the debris," he says after some moments of thought. "There are...pieces, that I could not remove on my own."