You might try installing the plugin via FTP. Extract the files from the zip. Then ftp the wp-google-maps-pro folder to the /wp-content/plugins/ folder on your webserver. You’ll need to activate the plugin from WordPress Dashboard → Plugins after the file transfer completes.
If the plugin does not activate after this, please let us know. It would be helpful if you could provide both temporary WordPress admin and FTP access to your site.
Create a temporary admin account for your WordPress site and send us the following information: