The chemical safety data sheet (SDS) for Formula 409® Multi-Surface Cleaner is readily available, stating it contains alkyl (C12 40; C14 50%; C16, 10%) dimethyl benzyl ammonium chloride, quaternary ammonium compounds. Unlike ethyl or isopropyl alcohol or similar cleaners, these alkyl compounds do not evaporate, and leave a thin film on the surface of the monitor. Further, they may be hygroscopic, "pulling" water out of the air into any electronic circuits they've onto which they've been sprayed.
Since you were careful not to spray the monitor itself, only the cloth, likely you've done no harm -- you can judge that yourself, if the monitor appears to be working. However, I'd follow up by using a cloth moistened with alcohol, distilled water or glass cleaner to remove the remaining chemicals.
Another question is the health effects of these compounds, such as contact dermatitis, asthma or respiratory symptoms, as well as long-term environmental and health issues. Of course, this is not the site for such a question, which might belong on Chemistry StackExchange.