In the end of Ad Astra, Clifford asks Roy to unhook him. Roy reluctantly obeys. But in the next shot, they show Roy staring at a bright near Neptune’s rings. Was it his own ship, or is there a possibility that Clifford may have somehow escaped?
If he didn’t escape, why did Clifford want to die? What was the point of it all, if he wanted to continue searching for life?
Clifford considers his mission a failure because he wasn't able to find other life in the universe. Also, he says that Earth is not his home anymore. Moreover, Clifford is a criminal, responsible for the death of his team. If he returns to Earth he'll turn from a hero to an insane villain.
It's unlikely that there's one more ship for Clifford to survive. If there were other ships nearby they'd be probably detected and inspected by Roy. Anyway, the bright object was too far to get to it with a spacewalk.
