When the form was published to the browser, the "display value" of the hyperlink didn't show, there was white space that was the appropriate size (it grew according to the number of attachments), but the display was blank. I went back and just dropped it in without a display (so the full url showed) and it was visible. Do browser forms not do will with hyperlinks when there is a display value?
The other side of it, the full url did not have the %20's in the path for the spaces, so even the non-display links didn't work. I know you can do a qrules command:concat("Encode /text=", attachmentURL) then show the results, to get those in there (Hilary helped me on a previous post on a single link a while back), but I couldn't figure out how to do it with the link being repeated from the secondary source. Would love to know how if you have the time :)
However, I found a work around... I made a button looking image and put it in with binding to the hyperlink. So, they can click the button to open the attachment. I put the substring formula that we tried on the display for the link, into a calculated value box to show the filename....see screenshot. It all works fine in the browser.