Can my Maltese employer report me to police over a workplace dispute?

Yes, verbal conduct during a workplace dispute can, depending on exactly what was said and how it was perceived, potentially fall within the scope of offences under the Criminal Code, Chapter 9 of the Laws of Malta, relating to threats or threatening behaviour, even where the underlying dispute is fundamentally a civil or employment matter such as unpaid wages, since criminal and civil issues can arise from the same set of facts and are assessed independently of each other. Whether what actually happened genuinely meets the legal threshold for a criminal threat, as opposed to an angry but non-criminal exchange of words during a heated argument, depends heavily on the specific words used, the context, and how they would reasonably have been perceived, which is exactly the kind of assessment that benefits from a lawyer reviewing the actual facts rather than assuming either that nothing will come of it or that a report will automatically succeed. In the meantime, it is worth writing down your own detailed account of exactly what was said and done while it is fresh in your memory, and separately pursuing the underlying wage dispute properly through the Department of Industrial and Employment Relations, since that civil issue does not simply disappear because of the criminal threat.