Not saying the OP did this, but many members do maternal incubation.
Not all maternally incubated eggs are as controlled as in an incubator. Not to mention, I doubt Africa is a place where the temps stay the same for 60 days.
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I doubt anyone will breed an eyeless snake based on ethics. But if incubation is the cause of eyelessness, then it wouldn't matter if it breeds since it isn't heritable. However, heritable eyeless snakes are a different matter....