Kosowski received both his undergraduate and master’s degrees from University of New Mexico, according to the Department of Health. He attended the medical school at Dartmouth College in New Hampshire, serving as the president of his class. Kosowski also received a master’s degree in business administration from Dartmouth’s Tuck School of Business. Kosowski began working at the Laufer Institute of Plastic Surgery in Dunedin in September 2016 and was involved in a medical billing dispute. Kosowski filed a civil lawsuit against people associated with the Laufer Institute of Plastic Surgery for negligence, breach of contract and fraudulent misrepresentation, seeking damages in excess of $15,000. Kosowski was taken into police custody on March 26 2023 after a traffic stop in Tarpon Springs. He faces a first-degree murder charge related to a missing Pinellas County lawyer, Steven Cozzi, according to the Largo Police Department. Cozzi's firm - Blanchard Law - represented many of the defendants in the billing dispute.