Hold him where and guarded by whom??? It's not like there's a secure CIA rendition facility in the middle of town. It's a group of abandoned cottages occupied by the PTA. Just trying to hold him in one of the houses is inviting escape and mayhem, and you can't spare people to do nothing but sit and make sure a prisoner is healthy and fed and secure until the interrogators are done with him. Why do you think Rick killed Porchdick? The whole rationale was "there's no jail to send him to!" It's not like they've built one since then.
Exactly. They are in a preserved, "normal" neighborhood, where the most security-minded features are a tower and sheet metal walls. This is not Woodbury, where barricades, prisoner / torture rooms and armed guards at every wall exist.
And you're right, just holding one of the wolves is begging for more trouble, since the only people there truly battle tested were few and far between (at the time Morgan caught one), and once again, there's nothing to be gained from crazed killers who have never been demonstrated to offer anything other than a brief word on how they will kill you.
Capture five (coherent) Wolves and interrogate them? What will you learn? That there's more of them in the woods and they want what Alexandria have and will be coming back soon. Carol already knows that.
...and they have previous evidence of their attacks and murderous nature. The Wolves are not a total mystery.
For some reason, the interrogation advocates skip over how removed from sanity the Wolves (encountered so far) are. There's no tactical advantage to basing plans around the ramblings of the insane, or someone being deceptive.
It would be as useful as Terminus Mary refusing to answer Carols demand to know where her friends were. An allegedly same (but malevolent) human refused to give any information--even after being shot--so why would anyone expect more from crazed killers?At this stage, the MO is take no prisoners, and this wolf guy probably knows that. He probably has a good idea that he will be killed, so why would he volunteer any information about anything? And what good is this information?