My wife being mentally harassed by IT company- Need advise

Hello Respected Sir/ Ma'am, My wife was working in an IT company for 3-4 months, she got an offer letter, she signed it and sent a copy of it to the company. When she joined the IT company, she didnt got appointment letter and after completion of probation period of 3 months, she didnt got confirmation letter as well. She asked for both the documents several times and honestly she got a typical India type unprofessional responses from the manager. In the interim she was getting mentally harassed a lot by the manager of the company when she used to ask for the 'change of seat, extra working of hours in company (9 hours was decided strictly for ladies maximum 6.30PM, but they used to make her sit and work extra purposely till 7.30/ 8/ 9pm), regarding appointment letter, regarding confirmation letter, salary slips'. When she left the company, she was the only employee who got her salary extra 2 days late because the company used to think that she will leave the company, so purposely they were delaying her salary by saying lame excuses of internet and bank issues. She had given interview in other company in between because of the above situations, now nothing is wrong in giving an interview in other company, its any employees freedom to give interview. Unfortunately when she gave an interview, the other company was little stupid, the manager called the present employer asking about my wife's feedback, and they gave negative reviews, quite a funny situation. since then my wife's company where she used to work started harassing her more mentally and delayed her salary as well. Honestly my wife used to work whole heartedly, she even used to get compliements many times. error in her work for negligible. She left the company immediately when she got her salary 'late', all her colleagues got it, and she was literally begging for her salary. Next day i said her to leave this stupid company and on her behalf i sent a note to their CEO and Manager that my wife wont be coming to your company from now on. The CEO replied that this isnt professional etc, i replied to him with a big email about her experience and the unprofessional responses the manager used to give when she used to ask for all her legal documents viz. apoointment letter, confirmation letter, salary slips and lastly her salary, work timings. On my email they never replied. Finally they sent a notice to us but before this they sent their clerk to verify our postal address without our permission and some gunda types person were also standing behind that clerk. i noticed that something is fishy, he verified whether my wife stays here or not by saying that he is from some courier company. When i called my wife's company whihc she had left before 3 months from this event, their CEO and manager denied that the clerk might have come to our residence 'BY MISTAKE'. funny, right? Finally we got a notice in whihc they mentioned that my wife used to work unprofessionally and were never happy with her work - To this point i will say, they must have fired her or should have sent her email as warnings, whihc they never sent. They are saying that my wife deleted some codes whihc gave the company a monetary loss in LAKHS and are asking us to pay them that ransome LAKHS of rupees becasue their company went in loss. and also mentioned in notice that without any further prejudice they want to prosecute my wife in criminal court of law for her illegal acts under provisions of Indian penal code of IT act and wants us to pay the monetary loss in LAKHS to them within 8 days. - To this i want to comment that, practically speaking all IT companies always have back up in theri servers, if any file is deleted the very next day the company comes to know that any single or sets of file is deleted, these people are harrassing us by saying that my wife deleted the codes and my question is, they are coming to know about this delete work after 3 months??? Honestly my wife deleted none of their codes, infact the codes were given to her by her manager, and she had no access to the server as well. how the hell the question arises of deletion. Can you pls guide us how to deal with this stupid notice where, honestly it is clearly visible that the company is acting completely unprofessional and are asking for their monetary loss and are claiming on us about code deletion etc (after 3 months). My wife was never given appointment letter, nor confirmation letter. They lose their client becasue my wife used to handle her work efficiently and seriously and when she left, they might have hired some other IT guy to work in her place, he might have failed to finish the work and henceforth they are claiming that loss on us, a complete act of unprofessionalism and harrassment. Can you pls share your valuable feedbacks PLEASE.