Shelley- how do you know they were infertile rather than killed though? Not hatching or developing does not automatically make them infertile.
Yeah, 16 is too many. Many hens will attempt to sit on a clutch way too large for them to cover adequately. Even so, many game hens are exceptional and are very good at keeping too many eggs under her pretty well compared to other hens. However, the rule still holds- if the nest is good and any eggs are visible while she is completely settled in, there is too many eggs.