This study focuses firstly on ascertaining if the Y-DNA 37 and 17 markers align with oral tradition of Zimbabwe and Mozambique that the father of one of the kings of these two countries originated in Portugal. Secondly the study aims at separating chieftainship that has been conflated with regards to the origins of kingship for the past 200 years. Thirdly the study aims to ascertain if the man cited as the father of the king was indeed a “New Christian” as per the oral tradition he left behind. Historical narratives regarding the Mwenemutapa Empire have long suffered from "The Great Conflation", a chronological distortion merging the 16th-century Mwenemutapa (king) Neshangwe Munembire (Mbire/Moyo) with the 18th-century Njanja Neshangwe (Sinyoro). This study utilizes a 37- and 17 marker Y-DNA Short Tandem Repeat (STR) panels to provide a forensic resolution to this 211-year discrepancy. Results identify a rare "Gouveia Signature" (DYS19=17, DYS385=15-18, DYS390=21) characteristic of the Belmonte Sephardic or Portuguese Diaspora. This genetic evidence, cross-referenced with 16th-century archival records, confirms a continuous 20-generation imperial succession originating from the 1505 Portuguese-Sephardic arrival in the African interior. Historical narratives of the Mutapa Empire often suffer from "chronological telescoping. This study utilizes high-resolution Y-chromosomal Short Tandem Repeat (Y-STR) analysis to provide a biological framework for distinguishing these two distinct historical eras. The 37-marker Y-STR and 17 Y-STR marker profiles were analysed and cross-referenced against modal haplotypes for Sub-Saharan (E1b1a/M2), Iberian (R1b-DF27), and Middle Eastern (J1/J2) lineages. Forensic comparison focused on high-stability "anchor" markers and fast-mutating "lineage-specific" markers to identify ancestral origins and subsequent genetic drift over 20 generations. The observed profile exhibits a categorical divergence from the typical Shona (E1b1a) modal. Critical exclusions include DYS19=17, DYS392=11, and CDY=33-33, which firmly align the paternal lineage with a West Eurasian, specifically Iberian, origin (R1b-DF27). Furthermore, a unique high-spread signature at DYS385 (15-18) and expansion at DYS389II (32) and DYS449 (31) suggests a prolonged period of genetic isolation and stable succession consistent with the Luso- African "Captains of the Gates" within the Mutapa court. The genetic data provides empirical evidence for a 16th-century imperial "firewall", demonstrating that the Munembire-Gouveia lineage is biologically distinct from the later Shona / Sinyoro Njanja expansion. This research highlights the utility of forensic genetic genealogy in reconciling oral traditions with archival records, offering a precise methodology for reconstructing pre-colonial African successions.