If your bread doesn't sound hollow can it still be done?
Absolutely, bread can be done without sounding hollow. We can make the analogy to a drum--if the drumhead is too loose, it won't sound hollow, and if the drum is full of something, it won't sound hollow. Similarly, if the crust is soft or if the inside of bread is undercooked and doughy, it won't sound hollow. 

That said, for many breads--especially those made with enriched doughs--a crisp crust and a stiff interior are not good indicators of "doneness". 

For a typical sandwich bread (one made with some milk, egg, sugar, and butter, like I expect your buttermilk bread is), it does often sound hollow when done. However, this is not a perfect (or even very good) test--even if it does not sound hollow, it may still be done.

The best test is to take a slice from the middle of the loaf after it has cooled. If the interior is too soft and doesn't spring back to shape when depressed, just bake a bit more next time--to 200F or 205F. Some more enriched doughs need to be baked to slightly higher temperatures.