I didn't include it because the SSA case that you describe isn't fully determined, it has 4 outcomes: one where the triangle is degenerate, one where a unique solution exists, but only if it's a right angle triangle, and in the third case there are two solutions, and it's not fully determined which one is "correct", because it's ambiguous
so, I wouldn't say it is fully determined! unless you presume specific side lengths and angles, which I didn't design this solver for. I've also never had a use case where I need to solve SSA triangles in practice so, shrug!