Does a bargaining agent have the authority to challenge an employer's decision not to reimburse medical advisors their professional liability insurance fees?

The bargaining agent also contends that the employer is violating article 5 of the SH collective agreement (entitled “Management Rights”) by deciding not to reimburse medical advisors their professional liability insurance fees under article 21 of the SH collective agreement. The bargaining agent agrees that article 21 calls for some level of management discretion. However, it submits that the employer’s discretion is not unfettered. The bargaining agent referred me to a number of principles enunciated by the arbitrator in Bell Canada v. Unifor, Local 34-0, 2016 CanLII 11573 (CA LA) at para. 46. Two of them read as follows: … 4. the exercise of management rights, both with respect to a provision in a collective agreement or generally, is an exercise of discretion which lies at the core of collective agreement rights and obligations; that is, the exercise of management rights is fundamental to the operation of a collective agreement; 5. as a matter fundamental to the operation and functioning of a collective agreement, any exercise of management rights discretion must be subject to challenge on the basis of reasonableness, or perhaps more specifically on the basis that the management right was exercised in an arbitrary, discriminatory or bad faith manner (which I believe effectively covers the field [sic] unreasonableness and good faith); …