Ok, thanks everyone who has looked at this. I've recreated the exact scenario for easy viewing at the link below, so I'll just comment out the original text I had as it wasn't clear. http://cpp.sh/5lp4l
In the comment section I show calling make_some(32, std::string{"hi"}) without specifying the Data type declaration for the call. I realize this seems insane and way above my expected use case, automatically inferring the composite type (inferring I wanted Data, based on the int/string) based on the arguments wasn't necessary, or a good idea.
The compiler is right. There's just no relation given between T and Args. Hence, it cannot determine what QueryResult<T> means.
What you apparently expect is that the return type of somefn forces T to be int, int. That's obviously not possible for two reasons: T denotes a single type, and there's just no mechanism by which the return statement somehow affects the template instantiation of make_some.