PHP League Jira OAuth2 mrjoops 3rd party package: experience working with Jira Cloud API?

Enhancing existing PHP/cURL (private) Jira Cloud ETL integration with existing AVC data-driven system by upgrading from authentication token to OAuth2. It is a nightmare of complexity. Best path forward appears to be mrjoops/oauth2-jira - Packagist. Seeking confidence to proceed by hearing from fellow developers of successful use of this OAuth2 package with Jira Cloud, or warnings about actual problems.