When Adding untagged items to the Structure, Indesign promptly states that Endnotes are not supported for XML tagging. I use XML tagging process for creating reliable Accessible WCAG compliant PDFs, and other export requirements. Please make Endnotes USEFUL - 1. keep in same story (not an additional frame) and make tagging process available.
OR... a way to convert endnotes to linked cross references - even in tables!
Tables if Indesign worst thought when it comes to footnotes and endnotes.