When you say she comes out in the evening, where does she go? Does she leave the nest? The coop itself? Some hens seem to have a strong roosting instinct and will brood during the day but become confused come nightfall. I've seen it more often in my chickens than turkeys, who are usually very fiercely broody, but it can happen. I would recommend trying to block off any roosts and keep her contained in the area where the nest is. You might also be best to switch the eggs in her nest with ceramic fakes for the time being, until she is fully broody. If the other eggs have been incubated during the day but left during the night, they are now dead and need to be thrown out.
