The high rate of retirement of older employees in organizations is a growing concern, and the trend is expected to continue, thereby leaving organizations with invaluable knowledge gaps or losses. Researchers have conducted various studies on this topic; however, there has been a paucity of studies on self-efficacy and organizational culture roles in determining the engagement of employee as it relates to the retirement of employees in organizations. Therefore, the purpose of this study is to examine the role of organizational culture and self-efficacy in organizations to achieve employee engagement due to the aging workforce and to ensure intergenerational knowledge transfer. The Watkins and Marsick’s theories of informal and incidental learning were used as a framework for this study. The theories frame the hypothesized conceptual model of employee engagement outcomes for the study. The systematic review of the relevant literature identified self-efficacy and organizational culture as key concepts of informal learning, and employees’ age for the potential outcomes of employee engagement. A 101-item survey was utilized to collect the data. The survey instruments were electronically sent to the pre-selected government agencies’ employees in the state of Oklahoma. The methodology for the study includes descriptive statistics, reliability analysis, and correlation analysis, multi-group structural equation modeling (SEM), mediation effects, and moderation effects. The hypothesized model has a clear and complete illustration of how self-efficacy, organizational culture, informal learning, and employees’ age affect employees’ engagement. The findings from the study provide empirical support to the proposed relationship between the variables and enhance the selected theories by offering additional empirical support.