An employee holding a managerial position is very likely not covered by the Employment Act, but if you want to use it as a guide, you may refer to Section 14 for the type of punishment you may give.
"14. Termination of contract for special reasons.
(1) An employer may, on the grounds of misconduct inconsistent with the fulfilment of the express or implied conditions of his service, after due inquiry:
(a) dismiss without notice the employee; or
(b) downgrade the employee; or
(c ) impose any other lesser punishment as he deems just and fit, and where a punishment of suspension without wages is imposed, it shall not exceed a period of two weeks.
2. About publishing in newspaper, you may have to check with your company lawyer;
3. I think you can still holding a DI if you think it's worthwhile. Getting evidence can be a problem. Consult your lawyer about it.