I'm reading a manga and having problems with a sentence. For context, one character just recommended going after the leader of the monsters so as to prevent more damage to their town from happening. The main character's response is:
I'm actually having problems with the entirety of this sentence, but especially 上を失えば. The only thing I've guessed after looking various things up may be that it means "losing again"? I know と言えど means something like "having said that", but probably because I'm confused about the beginning of the sentence I'm having problems parsing.
Since it's in the same sentence I'll quickly also ask about 烏合の集. I can't find any info (I'm guessing this is a saying), and Google autocorrects this to 烏合の衆. Can someone confirm that they mean the same thing? Thanks very much.