WordPress Migrator "cURL error 28: Connection timed out after 10000 milliseconds" error
This problem suggests that the connection from your host server to the SiteGround Migrator API cannot be properly established and times out.
To resolve this error contact your host and ask them to ensure that the outgoing connection from your server to the wp-transfer-api.sgvps.net hostname on port 443 is allowed and that the server can properly resolve the hostname.
After that restart the transfer process from the plugin.