How to handle the verification of an account in an application process

I'm redesigning an application process; the process has around 8 steps, each step varies in length.

At the beginning of the process, we ask the user to create an account by entering an email address and a password. The client doesn't want to make the user verify their account via email verification as he's concerned it will decrease completion of the application process. (User leaves the process to confirm their account, gets distracted and doesn't return).

There is a part of the process where the user must upload documents and the tech stakeholder is saying that it's a security risk to allow unverified accounts to upload documents.

Any advice on how to handle the situation? Thanks!