Can one customer see which answers we gave to another customer

No, customer A never sees the answers that went to customer B

No, that is not possible. Each customer has their own questionnaire, their own upload and their own submitted set of answers. What you filled in and confirmed for customer B remains in customer B's file. There is no shared portal and no overview in which one can see the answers of the other.

What does happen: the answers both come from the same supply chain file. If you give the same answer to customer A and customer B at the number of employees or the countries with establishments it is because it is the same source data, not because one has seen the other's list. Some information is also already public anyway, for example via the Trade Register — confidentiality cannot apply to that. For answers you prefer not to share separately, such as internal policy documents or scores on a control measure, the confidentiality button applies to that answer: with it you yourself determine whether something remains visible only internally or is included in what you submit.

Each submission is a separate file with the customer themselves

This follows from how the platform is set up: the system fills in a separate questionnaire per customer with answers from one central file, but the submission itself is made by the entrepreneur at that specific customer's portal. There is no link between portals of different customers, and Supplia itself never logs into a portal of a third party and does not read a submitted list. Which information is public anyway — such as the statutory name or the registration number — follows from the Trade Register Act 2007; for the rest, the confidentiality setting per answer determines what is visible to whom.