Theme explanation:
MRMARINER17AMoniker of the Seattle MLB player that won Rookie of the Year in 1984
[---------] is Alvin Davis,
TINDERSWINDLER22AMoniker of the Israeli conman featured in a 2022 Netflix documentary who scammed lots of women on a dating app, with "the"
[--------------] is Simon Leviev, and
THETRUSTBUSTER47AMoniker of the 26th US president that broke up many monopolies
[--------------] is Theodore Roosevelt... Alvin, Simon, and Theodore make up the
CHIPMUNKS55AThe first names behind the monikers of 17-Across, 22-Across, and 47-Across gets you this high-pitched, squeaky singing group, with "the"
[---------] who sing the "Witch Doctor" song (ooh eeh ooh ah aah ting tang walla walla bing bang)