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Hi poliedric, I seem to remember a situation when it was loading by ajax, could that be your case? that could explain you not finding it in the source code and GSC still showing you the tag. Info on extentions for finding ajax content https://stackoverflow.com/questions/7830864/jquery-load-data-not-showing-up-in-page-source I´m not a coder though so could be other reasons Hope this helps

No problem, if you have any other questions about getting YouTube videos to rank let me know! I would love to help.