May they delay for a long time the decision of a submitted manuscript of someone that already sent a paper which didn't pass plagiarism check?
The people who run good journals are (i) professionals, (ii) people. From the first follows that it's not professional or appropriate to sit on a paper for a year without sending it out to reviewers or making a decision as punishment. That's just not ethical. From the second it follows that the editor is probably not going to bend over backward to ensure the paper gets dealt with today instead of tomorrow. In any case, your characterization of editors as these kinds of vindictive monsters out to get you is incorrect -- that's not the kind of person who would be appointed as an editor.

Either way, there is nothing wrong with writing an email to the editor and asking what the status of a paper is. That happens every day, and it's part of the job of an editor to deal with this in a professional manner. So go ahead.