[6] At ZERO1 Sayonara West Holy Land Hakata Star Lanes on March 10, 2019, Iwasaki defeated Shogun Okamoto to win the United National Heavyweight Championship.

[7] He worked in cross-over events such as BJW/ZERO1 Clash I, a show promoted by both Big Japan Pro Wrestling and Zero1 on April 24, 2019, where he teamed up with Shoki Kitamura and Kohei Sato and fell short to Daisuke Sekimoto & Okami (Daichi Hashimoto and Hideyoshi Kamitani) in a six-man tag team match.

One of them is the Fire Festival and at the 2018 edition of the event he placed himself in the Block A, scoring a total of ten points after competing against Yuko Miyamoto, Masato Tanaka, Jiro Kuroshio, Shogun Okamoto, Chris Vice and Takuya Sugawara.

[10] At the 2019 edition of the event, he scored his best performance by winning the Block B with a total of nineteen points over Yuko Miyamoto, Masashi Takeda, Kohei Sato, Takuya Sugawara, Shogun Okamoto and Yasu Kubota.

[12] Another important event promoted by Pro Wrestling Zero1 in which Iwasaki took part is the Furinkazan Tag Tournament, making his first appearance at the 2019 edition, where he teamed up with Kohei Sato, defeating Yasu Kubota and Hide Kubota in the first-round, Masato Tanaka and Tetsuhiro Kuroda in the semi-finals, but fell short to Yuji Hino and Yuji Okabayashi in the finals.