If you mean, did your employers do anything illegal for which you can sue them, no, they did not.
If you mean, is your claim for $648 likely to be successful, no, I very much doubt it. There was nothing stopping you from filing for unemployment during your suspension. The law does not require that the employer fire you before you can collect - you could have filed during the unpaid suspension. If you did not do so because you thought the employer had to use the word, fired, that's not the employer's fault.
Two things I am tired of typing: 1.) A wrongful termination does not mean that you were fired for something you didn't do; it means that you were fired for a reason prohibited by law. 2.) The above answer, whatever it is, assumes that no legally binding contract or CBA expressly says otherwise. If it does, the terms of the contract apply.