Is it getting all the way through or is there an error at the end?
It is getting all the way through, the last message is this:
"Usuário inserido xxxxxxx id xxxxxxxx"
that means: "User inserted xxxx id xxxxxx."
I looked the log and I didn't see any errors in the end...
There is only a warning in the beginning: "PHP Warning: Module 'zip' already loaded in Unknown on line 0" but I don't know if this is important.
Can you have a look at the database logs? Moodle uses a database transaction to insert the users. If for some reason the transaction is not committed, all the inserted users will disappear as soon as Moodle closes the connection to the database.
 That doesn't leave a trace in the PHP error logs. Just in case, make sure you set Debugging setting to Developer level, to get the maximum amount of detail in your PHP error logs.
thanks for the tips... we looked the logs and discovered that we needed to increase memory limit. After doing that, restarting httpd and the database (there was a lock in the table too), and enabling TLS, it worked!
Thanks for the help, people!