Appears to me the sign violates none of those.
Next case!
If Joey is found "guilty," anybody know if there is an appeal process?
Sure, he appeals through the administrative process, and then he can bring it to the state courts to appeal, and then to the federal courts challenging the constitutionality of the regulation and/or of its application to him and his sign.
Joey Vento has plenty of money to pursue appeals, and will certainly do so...all the way!