Hm, is it that you want those URLs converted into actual attachments in Airtable?  If so, try using an automation to paste the dropbox URLs into the attachment field

I believe the with make.com the image are link urls using cloudconvert .  As you can see above the test the techician did and screen show it worked for them but when I login it do see them at all 

Oh, when you look at the record’s revision history it’s going to show you who deleted those.  Are you able to trigger the Make automation again to get the data to re-populate?