My app replaces default Shopify's checkout process with own, therefore Shopify itself doesn't know if the checkout was abandoned or not.
Is it possible to insert abandoned checkouts over API as I dont see it in official documentation? Perhaps there is workaround I could use?
The reason I wanna insert abandoned checkouts is because my users use abandoned carts recovery apps.
No, you can not create abandoned checkouts via the API. If you want to have an abandoned checkout - don't skip the Shopify checkout.