Process evaluations help to understand and refine health interventions. The “ISAC” intervention targeted the enhancement of early detection and prevention of oral cancer (OC) through tobacco-cessation counseling, patient communications, and ISAC role-modeling. Over six months, throughout ISAC implementation in the Jazan region of Saudi Arabia, Linnan and Steckler’s process evaluation framework’s specified indicators were assessed, by mixed methods, on context, reach, dose delivered, dose received, fidelity, recruitment, and participant’s satisfaction. Findings showed that 47 of 80 (58.75%) eligible dentists were reached and received all components. Thirty-six (76.6%) participants reported reading all intervention materials, visited the ISAC website, scored high on the perceived quality of provided information (M = 4.62 ± 0.63), and provided support (M = 4.67 ± 0.57). The fidelity was scored high across all intervention components. Role-modeling of the ISAC had the highest satisfaction score (M = 9.77 ± 0.58 out of 10). High perceived-effects were reported in relation to feeling confident in performing OC examination and training patients on OC self-examination (3.95 ± 0.22). The intervention attained high implementation levels for dose delivered, dose received, and fidelity. The intervention delivery was associated with high satisfaction and perceived effects. Using multiple data sources enhanced the understanding of the implementation process and strengthened the validity of the study’s findings.