So I replaced the check valve with the OEM Jandy part, whole assembly, not just the flapper. Problem solved. I used this part (same link) as in original post. https://www.amazon.com/Zodiac-7056-Flapper-Assembly-Replacement/dp/B008E6SZS6/ref=psdc_9425947011_t1_B07XTPF915

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Replacing the newly installed knock off part:

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https://www.amazon.com/gp/product/B07XTPF915/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1

Next time, I will remember.