Ben's cane was cut in half by the sword. After that he's seen walking with the same cane.
When Hannah activates the accelerator, the magnetic field it generates is strong enough to pull the saber out of Donovan's hand, yet Ben's metal watch chain is unaffected.
Ben tells Hannah that after he helps people, he leaps away and never sees them again. In Judgment Day (2023), a major part of the story involves Ban and Leaper X retracing their previous leaps, wherein Ben does revisit several of the people he'd previously helped.