I use this plugin with WMPL, but WC Catalog Enquiry plugin settings don’t save my choose in both languages (it/en).
I need to exclude a category from catalogue, but if I select that category in english, when I change language I lost this.
I have the same problem with custom button label (I lost text in one language).
We need to check the WPML settings, can you share site access (it will be better if you will share the staging site access), admin and ftp access.
While sharing the access, don’t forget to mark the response as private.