Gola is stated in the same Purana. Gola: (gola) refers to sphere or globe as the celestial globe or as the globe of the sun or of the earth.
Unfortunately the confusion only lies in someone without knowledge of the fundmentals reading such a text and taking what they want from it from their own bias.
The example of the flat earth in the text is being used as an example to understand from a different vantage point, that is all. The text does not state that the earth is flat.