(Looking for an API)Is there a way to access issues fixed through a particular merge request instead of actually closing them and retrieving by using closes_issues api

My requirement is to fetch list of issues that will be fixed once particular merge request is approved. I have tried using closes_issues api…Obviously it closes the issues if a particular pattern is used. But I want my issues to stay open (until validated by QA).

By disabling auto closing of issues closes_issues api is no longer valid and hence does not solve my case. I have been doing quite a bit of research but couldn’t figure a way. I could really use some quick help. Thanks in advance