#5 Chad Gable

Chad Gable is one of the most talented young performers in the WWE, and alongside Jason Jordan, he was once compared to team Angle, and given that Jordan has been out for over 12 months with an injury, Chad should step into that role.
If Kurt's 'son' Jason Jordan were to be healthy, that would be the much better option, but given that Kurt is a prolific amateur wrestler, Gable is a great candidate.
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Chad has all the in-ring ability and charisma in the world, and if he's given the push he deserves, he will become a big star, so being the one to retire Kurt would be a great start to that push.
Although it won't be to this level, this could play on the HBK/Ric Flair retirement type match, where someone is given the chance to be the final match in their hero's career, and this could be the match that starts a main event push for Gable.