First, punch card for others is a misconduct. What disciplinary action to be taken depends on the company's policy. Even they want to terminate you, they can't just give you a termination letter and ask you to go. There is due process to follow, i.e., show cause, domestic inquiry, etc to give you a fair chance to defend yourself.
If they didnt do that and terminate you, you can report to Industrial Relation Office and ask for reinstatement/compensation.
However, if the company confirmed that you are guilty and decide to terminate your service...(helping other to punch card could be perceived as integrity issue, which is quite serious), they have the right to do so.
BUT, they can't terminate you alone but to keep the others who involved in teh same misconduct. Have to follow the same process. Else you could again report to IR Office for unfair HR treatment.