@lalajee, Thanks for posting in Q&A.
Based as I know, to publish new version private apps from managed Play in your EMM console, we will click edit to upload the new version to replace the old one. So I think it's not able to keep the both version.
https://support.google.com/googleplay/work/answer/9146439
Note: Non-Microsoft link, just for the reference.
But the app update is basically a process done entirely by Google, Maybe you can visit Google Play help center by clicking Managed Google Play Help or consult the Google team to know if Google have method with testing new version, i
Thanks for your understanding.
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