It seems “open source” means different things for different people.

If you could see the code but were not allowed to redistribute it then I’d call it “source-available”… but you can redistribute the code, in this unusual case.

Forbidding reselling to any degree makes it “non-free” (as in freedom), which is the important part. The term “open source” was created to speak about “free software” without the moral or political aspects of user freedom.