I feel instead of mentioning this in writing one should ensure to inform / communicate to the employee verbally that, he shall be barred/ blacklisted from appearing for the interview in yur company for next 2 years. Sounds more resonable. Few things should be kept verbal.
Hope this helps!
Do not write any such command. While you need to keep 2/ 3 shortlisted candidates for the position, I suggest two step methodologies here below::
1) Initiate corrective steps to make your company join. Conduct survey , execute steps needed as systems and culture improvement. There are companies, its remuneration is not big, but work culture , training, HR practices are very good and management is humane and people focused. See a report interview of Tata's concern.
2) You can stop salary negotiation at previous employer or new places by not mentioning any remuneration details. Just share the payable details in length but make it verbal. The appointment letter you can give once he joins along with relieving letter and on submission of other documents say on 3rd or 5th day in presence of his HOD.