Based on fsQCA and multi-case tracking data from 15 private colleges and universities in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA), this study explores the generation mechanism of educational confidence in private colleges and universities under the dual tension of market logic and public welfare logic. The empirical results show that: (1) The formation of educational confidence presents three differentiated paths: mechanism synergy (synergy between resource coordination support and industry relevance), market-responsive (dynamic matching between spatial embedding and industrial resources), and ecologically symbiotic (coupling of three elements: institution-resource-space). Among them, the critical value of industry relevance (0.7) has a significant impact on the improvement of educational confidence (β = 0.42, P < 0.01); (2) Private colleges and universities realize the transformation of development paradigm by constructing a three-dimensional mechanism of “resource reciprocity-spatial coordination-institutional innovation,” and typical cases show that the employment rate of their graduates in the GBA has increased by 28%; (3) Cross-border industry-university-research cooperation enhances the institutional legitimacy of educational confidence through the knowledge transfer effect (path coefficient 0.67). The study proposes suggestions such as constructing a GBA-characteristic industry-education integration evaluation system, providing a theoretical reference for the governance of private higher education.