A winding, tortuous case that has dragged on for nearly 18 months has seen a US consumer electronics firm fail in its legal pursuit of an Irish employee after he left the job. However, in the process, the company scuppered two new jobs for the man at other companies, all while he racked up legal costs. Zagg, the maker of mobile phone accessories like power banks and screen protectors, has been in a legal tussle with an Irish ex-employee, Dermot Keogh, in the US over his departure from the company. A court order, issued earlier in April, came out in…