Files Not Downloading With Double Click

I work on a team of 7 people, in which 5 people have issues with smart sync.

I am one of the 2 where Smart sync behaves as expected: when you double click an online only file, it opens instantly. 
I use 3 computers and 2 Dropbox accounts (the business and the personal), and for me, it works as expected in all of them (Big Sur and Catalina OS systems. 2 computers connected by cable, one laptop by wi-fi. 2 of the computers are from the company, therefore with more security issues, one is a personal laptop).

My other colleagues need to right click and select "local" before opening a file (they are using company macbooks and imacs). 

If they try to double click it, they will get an error message. (attached)

This becomes incredibly annoying when working with Indesign documents that have hundreds of links inside. 

My colleagues need to go file by file clicking to make local (or make huge project folders (50gb plus) available local.

We already contacted Dropbox support and the suggestion was to reinstall the app, then they closed the ticket.

The IT department of our studio also tried all sorts of troubleshooting without success.

we did all of these:

logout dropbox, restart, login dropbox
uninstall old dropbox with app cleaner
install new dropbox
tweak configurations of dropbox (activate and desativate extensions on mac permissions)
uninstall indesign
install older version of indesign

install most recent version of indesign

none of these steps solved anything. 

I read most of the posts on the forum with similar issues but couldn't find anything that worked.

status on bar is all files up to date.

can anybody help us with this incredibly annoying issue.

thanks