I initially converted my spreadsheet data to PDF and brought the PDF into DT. This is awkward to search when the spreadsheet PDF is longer than one screenful.
Now I’m trying something different. I’m using the spreadsheet’s ability to export to HTML to create an HTML version of the spreadsheet. Then I bring that into DT as a Rich Note. The matrix is lost, but all the information on a spreadsheet row is at least kept together, and searching is faster and more convenient in DT.