Seems I cannot find two people to agree on Illinois law regarding non-compete.
The enforceability of a noncompete agreement depends on the specifics - the specific terms of the agreement between employer and employee, and the specific conditions under which the employee was employed by the first employer and the specific conditions under which the employee will be employed by a new employer.
I am not understanding the preliminary injunction. Are prospective employers refusing to hire, or is a current new employer threatening to terminate employment, because of the existence of an old noncompete agreement?
I recommend you rely on information and advice from your attorney because your attorney knows your situation.
Good luck.