I believe the consent dialog and the App Tracking Transparency dialog are different things. Apparently, Apple don't like when consent dialog is shown before the App Tracking Transparency dialog.
Try changing "Location To Show User Consent" setting to "Nowhere". And if you need to show the user consent dialog for people in EU - do it later in the game, after the "Request IDFA" action.
As for the buttons in the consent dialog - you can show your own dialog instead of the default one.
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I haven't tried this myself, but I too will need to release an iOS app soon, so please let me know how it goes.