Recognition and redundancy
A. No you cannot insist. Section 188(1B)(a) of the Trade Union and Labour Relations Act 1992 (TULRCA) only entitles the union to represent employees at risk of redundancy who are in the bargaining unit for which the union has representation rights.
Your union has no right to represent workers outside the bargaining unit in the consultation, and no right to win a protective award for these workers if that consultation is defective.
Instead, the employer must allow these employees to elect their own representatives from among the group of at-risk employees who are outside the bargaining unit.
The election process must comply with the detailed rules found in Section 188A of TULRCA. There is nothing to stop union members standing for election, as long as they belong to the group of at-risk employees who are outside the bargaining unit.