I am confused about your description in paragraph 2, "rear stay". Chain stays or seat stays?

In any event, I think your question in regards to whether or not this frame can be of resale value in a repaired state is a rather risky proposition. Does your profit margin on this "repaired frame" cover the cost of worrying whether or not someone may have been killed while riding this bike that you have repaired whether or not you had a disclaimer? Why not sell it in the state that it is in and let someone else do the repair for their own enjoyment to ride or display in their home or shop. You will alleviate any problems in that way.

As for myself, I would never ride a bike that is glued together, whether professionally or by a home hobbyist. Just my thoughts. You made your money or will make your money on the parts.
I built a tandem frame about 10 years ago and I get offers to sell it all the time. I never consider it just because I want no liability, even though I've been riding it for a decade. It is probably safe, but I will not take any chances on someone getting hurt. If I hurt myself, that's my problem/fault.
Since you asked, no way! Sell it as is!

I know there are some strong epoxies. JB weld is very strong, but I still wouldn't trust a bike like that. Probably there are stronger epoxies now but I feel ridiculous to try to recommend gluing this bike together, so never mind. Bad idea all the way. Maybe I'm just getting old and no longer a risk taker like 20 years ago. Crashing on bikes at full speed HURTS. Breaks bones too! I've had my share.

List it on eBay. Someone will buy it. You'll probably sell it for more broken than fixed anyway. People just love projects.