Exec dependecy cant install plugins

We are starting a journal by installing OJS in version
However when trying to install a plugin (ex. Quicksubmit) the error appears:

“The “exec” PHP function has been disabled on your server. Contact your system adminstrator to enable it.”

So we installed this plugin manually and apparently it worked. But I read here on the Forum that manual installation is not advised.

Our host’s support says that the PHP ‘exec’ function is disabled for security reasons and suggests using the Phardata library.

I found a post that deals with this, but apparently there are dozens of changes:

And here it is said that OJS version 3.4 will solve this problem:

We request more information to help us make the best decision(?):

-Wait for version 3.4
-Continue installing Plugins manually
-Try to make code changes to be able to install and update Plugins
-Install version 3.3 (would it solve?)

Thank you very much for any suggestions.