Howto capture the events of signing complete/opt-out in native webview iOS

Hi, In our native iOS app (Swift), we get signing sessionToken from our own endpoint, and then launch webview with the URL like: https://sandbox.e-signlive.ca/access?sessionToken={sessionToken} for signing ceremony. Previously, we capture the redirection events after the ceremony finished and goes back to our logic. But those events were eliminated a couple of months ago from eSignlive side. A workaround version was provided and eSignlive suggested us to use SDK to handle it. Now we get a chance to try eSignlive SDK, but so far didn't find any way to resolve this issue. Would you please advise? Thanks a lot.