So adding him to the trust list is not unreasonable. But if he ever gives me a trust it looks like a self scratch.
Not sure I get that part. If he gives you a positive rating later? That's not on you. That's not what's being discussed in this thread.
Since you can frame any one as a self scratcher if you have access to their trust list.
Everyone's trust list is public:
https://loyce.club/trust/2020-12-05_Sat_04.07h/64507.html