As a freshman in 2021, Kacmarek took a redshirt. Over the next two seasons in 2022 and 2023, he appeared in 27 games, where he hauled in 42 passes for 507yards and two touchdowns. After the 2023 season, Kacmarek entered his name into the NCAA transfer portal.
Kacmarek transferred to play for the Ohio State Buckeyes. In 2024, he played in 12 games and brought in eight receptions for 86 yards as Ohio State won the nationalchampionship. After the 2024 season, Kacmarek returned to Ohio State rather then entering the NFL draft. In week 2 of the 2025 season, he hauled in two passes for 55 yards and a touchdown in a win against Grambling State.