Angor expected such a decision from his professor.
The outer city might be dangerous, that much was true. But how dangerous compared to the real Nightmare Realm? The darkness was likely brought by something from the Nightmare Realm, and Sunders, as someone who explored Nightmare Realm multiple times, did not need to fear it at all.
Sunders came and listened to extra information so that he could hopefully learn as many clues about the condition as possible. It seemed there wasn't much to find out here, so Sunders made up his mind to dive into the darkness himself.
Angor considered his options.
"I'm going with you, sir."
"You can, but you will stay inside my gravity garden until I'm sure I can guarantee your safety outside."
Sunders wished to get into the darkness because he was confident in escaping should anything forced him to.