I searched the Michigan statutes and here's what I found that fits your factual scenario:
750.414 Motor vehicle; use without authority but without intent to steal.
Any person who takes or uses without authority any motor vehicle without intent to steal the same, or who is a party to such unauthorized taking or using, is guilty of a misdemeanor punishable by imprisonment for not more than 2 years or a fine of not more than $1,500.00. However, in case of a first offense, the court may reduce the punishment to imprisonment for not more than 3 months or a fine of not more than $500.00. However, this section does not apply to any person or persons employed by the owner of said motor vehicle or anyone else, who, by the nature of his or her employment, has the charge of or the authority to drive said motor vehicle if said motor vehicle is driven or used without the owner's knowledge or consent.
This statute is commonly referred to as the unlawful use of a motor vehicle. Additionally, as you can see, it is a misdemeanor, not a felony.
I also located the information on obtaining the CPL. To obtain the license, you can't have been convicted of any felony offenses or of certain misdemeanor offenses. However, this offense is not listed as one of the misdemeanor offenses that would exclude you.
The only logical conclusion is that they have your information wrong. I would suggest obtaining a copy of the judgment and sentence from your case, you can get a copy from the clerk of court. Provide it to the licensing board and they should clear you for the CPL.
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