Since signing a three-year, entry-level contract with Vegas in July of 2019, Kallionkieli has yet to make it to the AHL level.
The 2019 fifth-round pick has spent most of the 2023-24 season playing in Poland with STS Sanok, where he has scored four goals and accumulated 10 points in 16 games. It seems probable that he will continue playing overseas for the rest of his career.