There’s a recaptcha plugin available on the Marketplace at https://marketplace.mendix.com/link/component/115762, I’ve been using it recently for a form I’ve been building – it comes with a usage example that can be copied to set up what you need. 

Hi,

You can drop a nice email to the developer of the widget , as per my experience and  in most case, they can help you by upgrading and releasing to latest version.

Next is build your own solution .

Hope this helps.

Cheers