It is not so much as new vs existing…
It is not uncommon for plugins to need the file in question to ensure the tables that it requires are up to date. This is what Connections is doing. It is checking that the tables are current so it know of it needs to runs any db upgrades or not.
It could be that the other existing plugins do not have any database tables. So there would be no need for them to load that file and would not generate a error.
Since you’ve updated Connections in the past without issue, I suspect that GoDaddy may have changed something on their servers which is causing this issue for you. I would suggest contacting GoDaddy support to let them know of this issue. Perhaps this is something the can quickly correct.
Also, if you send me an FTP login, I can take a look at the permissions of the files and tweak them so the files can be loaded by WP.
I’ll also need a temp WP admin. You can use this plugin to create it:
I do not think it requires any database tables so it should install and work without any issues.
Reply back, as a private reply, with the login details for FTP and the temp WP admin login link.