1. I don't think you can place an XLSX sheet into an existing table. If you import an XLSX sheet, it's treated just like imported text; you can either place it as a new object (a text frame containing a table containing your data) or use the 'replace' function, which will effectively empty out an existing frame and place the new text (/table) into it.
2. textFrameEdd = docEdd.pages.item(0).textFrames.item(0).words.item(0).applyParagraphS tyle(docEdd.paragraphStyles.item('INDENTparaBody'))
That ought to work -- but "applyParagraphStyle" does not return any value, it's just a function that applies the settings immediately. It returns 'void', meaning, your variable textFrameEdd will be set to 'null' (or 'undefined' or sth).
A small note is you don't have to target a word, since paragraph styles can only be applied to entire paragraphs. Personally, I'd use the shortcut "direct indexed" form  rather than ".item(0)", so I'd probably write this as
An alternative is this, by the way:
docEdd.pages.textFrames.paragraphs.appliedParagraphStyle = docEdd.paragraphStyles.item('INDENTparaBody');
3. Per 2., your variable is cleaned out, so you cannot use it anymore. Furthermore (and more important), you cannot apply a table style to text, which it seems you are trying to do. You should target the table itself instead:
docEdd.pages.textFrames.tables.appliedTableStyle = docEdd.tableStyles.item('altROWtable');
Thank you so much for your help. Cheers.