Yes, because in some unions, the President, working president, etc., who are office bearers of the union, can be outsiders, and the management allows them to participate in talks.
The employee whom the management has suspended is still on your rolls. You will be paying him a subsistence allowance. Once the domestic enquiry starts, you have to allow him to take part in the enquiry. The employee is under suspension but not terminated. Even if terminated, if the unionized workers elected him as an office bearer, then it is mandatory to allow him to participate in talks.
Regards,
Kamesh