Usually, a normal pinhole is too dim for comfortable viewing on a 4x5 ground glass. Even in bright light and under a dark cloth, you may see little or nothing useful. So yes, your expectation was understandable, but in practice composing with a regular lens of similar focal length is often the more practical method.

A known workaround is to use a much larger pinhole for composing, then switch to a near-optimal smaller pinhole for the actual exposure. That can make the image bright enough to frame, especially with experience under a dark cloth.

So the short answer is: you might see something under ideal conditions, but not reliably. Composing with a lens, or using a dedicated larger composing pinhole, is the practical solution.