In February 2020, Jowash was invited to Japan by Onose Sensei for rigorous training under 8th and 7th Dan senseis. This experience refined his skills and teaching methods, enabling him to guide students from beginners to advanced practitioners. During this visit, he successfully earned his 1-Kyu certification under the All Japan Kendo Federation.

The pandemic from 2020 to 2022 disrupted shinsa opportunities but not Jowash’s dedication. His efforts were rewarded in 2023 when he returned to Japan, passed his 1st Dan examination, and continued his training under renowned Senseis. That same year, he observed a prestigious tournament at Mito Tobukan Dojo, an unforgettable experience shared with 8th Dan masters.

In 2024, Jowash, together with Onose Sensei, the club was renamed "Negros Shiseikan Kendo Club," with the dojo's name reflecting its guiding principle: "The Highest Sincerity." Later that year, he achieved his 2nd Dan under the All Japan Kendo Federation. Under his leadership, his students won championships at the 6th Philippine National Kendo Tournament, a proud milestone for the growing kendo community in Negros.

Jowash Saballero’s journey is a testament to his unwavering commitment to excellence in Kendo. Guided by Onose Sensei’s teachings, he has learned the Japanese Kendo while fostering a new generation of practitioners in Negros. His dedication continues to inspire and shape the way of the sword in the region.