Add resources to a task that affect the duration of the task, but not the cost?

Objective: We would like to add resources to a task that affect the duration of the task, but not the cost.
Constraints: Project costs cannot change up or down.
Example: Task with multiple resources assigned.
• In this hypothetical, three resources of different rates have been calculated to form a unique blended rate per hour.
• Additional resources must be added to compress the timeline.
• We would like the behavior of a “Cost Resource” (static cost) but function like a Work Resource (affect duration as well as start / end dates.

Can it be done?

Thanks in advance for your help.