Return multiple email addresses defined by role

Hello, I want to notify people through an automated workflow. The notification should be sent to persons related to a certain role and the role-name list is stored in a separate sheet. There can be a single name or multiple names. How can I join contact values, so the joined values will give email addresses? The join function doesn't seem to work:

=JOIN(COLLECT(Name:Name; Role:Role; "LOG-SAP-pricing"); ",")

the names are transferred, but not the email addresses (like First1 Last1,First2 Last2).

I want to receive a cell value containing a single or multiple email addresses, which can be referenced in a workflow.

Many thanks