Probation Termination

An employee was hired for a particular Job role which included customer handling also and he was in the Probationary period. During the probation period he declined to speak to customers, most of the time he was at home and when he was asked to come to office he used to report 2 - 3 hours late and used to sit idle for 4 - 6 hours (his total time at work). When task were assigned he has instances of insubordination against him and wilful negligent work is also seen in his work. The service agreement clearly states the below : In case you have been fired by the management due to lack of performance or your work has not match up to the mark of the management, your salary/expense won’t be paid* Performance Clause : During the course of your employment you will be evaluated/ assessed on the basis of your performance of your employment with the company. The company at any time shall withhold your remuneration/receivables, if it is of the opinion that your performance/or your effort was not genuine to the tasks/targets so provided to you at the inception of month. It is also stated that the company is not obliged in any manner to pay your remuneration/ receivables that is outstanding if in that particular month/time span your performance is not up to the mark. And the employee has agreed to it and has signed and returned the agreement. Now he has been fired from his services. Is the management still liable to pay his salary, as he is now threatening a legal case?