I assume that you can open your
seedbox in FTP/SFTP via filezilla as per above
Go to the folder that hosts all your downloaded content, highlight them all, then right click on one of them and make the selection "Copy (URLs) to clipboard.
Open Excel "If you have and paste the content there" , then use "text to columns" and set your width as next column just before your file name starts, in my case it would be here "/files/downloads/"HERE"Oceans.Eight.2018.MULTi.1080p , all your files / folders would be in each row.
From your torrent client, do also an export of all your current seeding torrents, it will also give you a list of all your torrent names, paste those also in a new Tab in Excel.
In Sheet1 you should have all your FTP names in column 1 and on Sheet2 you should have all your seeding torrents name.
In Sheet1 you should then do a VLOOKUP against Sheet1,Row1,Column against Sheet2, Row1:Row"Where It Ends".
An example of the vlookup command should be something like this on Sheet1,Column3, Row1: =IFERROR(VLOOKUP(A1,Sheet2!A$1:A20000,1,FALSE),"To rrent Deleted")
Thus, if a torrent name is not found from your FTP list against your seeding list on Sheet2, it will mark it with "Torrent Deleted", else, if it is still seeding, it will show the torrent name.
I hope this helps
