Before joining the Bulldogs as a freshman in the 2020–21 season, Kaiser was selected in the 2020 NHL Entry Draft, in the third-round, 81st overall, by the Chicago Blackhawks.
[2] Following his junior season with the Bulldogs in 2022–23, Kaiser opted to conclude his collegiate career by signing a three-year, entry-level contract with the Chicago Blackhawks on March 15, 2023.
[3] Reporting directly to the rebuilding Blackhawks roster, Kaiser made his professional and NHL debut in a 4–2 defeat to the Arizona Coyotes on March 18, 2023.
Kaiser represented the United States at the 2022 World Junior Ice Hockey Championships, where he recorded an assist in the opening round-robin game before the tournament was cancelled due to the ongoing COVID-19 pandemic.
He later returned for the revised tournament and posted 2 goals and 3 points as Team USA finished out of medal contention in 5th place.