It might be clientlib dependency is causing this issue.
We can refer below steps to troubleshoot the issue -
1. As you are facing the said issue with few pages, were those page created with same template?
if yes, then please check page rendering component via sling:resourceType property at jcr:content node
of page.
Check what are the clientlibaries are getting used , dependency client libraries like below one -

and compare with dependency client libraries associated with pages where you aren't seeing this issue.
2. Regarding babel-polyfill issue please refer below links -
https://stackoverflow.com/questions/53287691/uncaught-error-only-one-instance-of-babel-polyfill-is-allowed-error-on-producti
https://github.com/babel/babel-loader/issues/401
https://stackoverflow.com/questions/43902416/only-one-instance-of-babel-polyfill-is-allowed-error