From your narration, it is discernible that you are only a contract employee to the client of your employer who had already satisfied with your back ground before and after your appointment under them.Therefore, it is quite unwarranted for the client to conduct a further BGV and find some discrepancy according to his subjectivity. Even if the client sticks to his subjective assessment, at best, he can ask for a replacement only. If your employer ( HCL ) tries to fire you on the subjective misconceived findings of the client, it is a bad HR practice as well as an illegal termination. I don't think it will cost your job. Any way, try to positively convince the client to whom your services are lent and keep the HR of HCL Technologies informed in this regard.
Secondly, most companies do ask employees to leave due to non-performance but to secure their further next jobs, issue relieving/experience letters. If you have the same, then you dont need to worry, show the same to your HCL HR and tell him that he took you onboard on basis of submission of all docs first.
Convince the team that previous employer is getting back at you for no reason. It took third party org 5 mths to get the feedback?? You have given your precious 5 mths time to HCL BUT if you have submitted any fake docs or if you have hidden facts that can lead to your separation with immediate effect, then we might have a problem.
Thanks and Regards,
Many companies give the similar reply to the BGV hence it is not a discrepancy but it is open to interpretation.
Experience letter is also relieving letter. many companies issue only experience letter. So far your documentation is concerned it is in order.