This paper presents an enhanced version of SDF-FuzzIA, a hybrid and modular system designed to support decision-making processes in geo-thematic domains. Built upon the Sustainability Decision Framework, the system integrates fuzzy ontologies, fuzzy rule-based systems, and a large language model equipped with Retrieval-Augmented Generation capabilities. The proposed architecture aims to deliver accurate, explainable, and semantically grounded answers to complex queries involving geopolitical, economic, and environmental indicators in alignment with the United Nations 2030 Agenda. A novel contribution of this work lies in the adoption of a Multi-Criteria Group Decision-Making methodology to support the construction of fuzzy ontologies, enabling the collaborative selection of membership functions and reducing subjectivity in knowledge modeling. Preliminary experiments show promising results in replicating expert reasoning, while highlighting challenges related to scalability, consistency, and automation. This approach lays the groundwork for developing intelligent systems capable of transparent and context-aware decision support in data-rich and uncertainty-prone environments.