Fatal error on activate

I purchased the Recaptcha plugin only to realize the version currently published (1.1.3) is not compatibly with the version of GeoDirectory I am currently using (1.6.8). I get the following error upon activating:
Fatal error: Call to undefined function geodir_resave_settings() in /nas/content/staging/aeromt/wp-content/plugins/geodir_recaptcha/includes/gdcaptcha_functions.php on line 20
This link would indicate that I am one version shy of having the above function:
https://wpgeodirectory.com/codex/codex/geodirectory_functions/geodir_resave_settings/

We are not in a position to upgrade the site at this moment, though would like to stop the flood of spam accounts, until we can upgrade this Spring. Anyone has any suggestions? Thank you for any help you could provide.