Hello,
Thank you for creating a bug report and including a replay.
As it stands, Arcray is working as intended.
Per the Yugioh Official Rulebook on the section of “Special Summon with a Card’s effect”, a card must properly be summoned by its summoning criteria in order to be special summoned by a card effect. Since the Arcray was summoned via the Soul of the Supreme King, it was not properly fusion summoned or summoned by its own proceedure. Soul of the Supreme king summons it “ignoring its summoning conditions” but does not treat it as a fusion summon. Because of this, it is illegal to attempt to special summon the Arcray from the pendulum scale as it recognizes its was not properly summoned from the extra deck.
You can find this ruling in the Official rulebook page 25 (PDF Page 15) located Here: https://img.yugioh-card.com/en/downloads/rulebook/SD_RuleBook_EN_10.pdf
If you have any questions, please feel free to ask in the #rulings channel of the Duelist Unite Discord server.
And thank you for helping to make YGO Omega be the best it can be.