Your link is broken for me.
From https://support.wero-wallet.eu/hc/en-us/articles/25599098295... it seems they don't even support phones with developer settings turned on, much less custom ROMs, rooted or jaibroken phones.
And android will actually turn off certified state if you install open source apps that were not signed by a registered developer
It works on a Pixel 6a with GrapheneOS.
And android will actually turn off certified state if you install open source apps that were not signed by a registered developer