Is there a way in Groovy to getEvaluatedMembers / get ancestors with Administrator permissions?

Summary:

Would like to know if there is a simple way of using getEvaluatedMembers (or similar) with admin permissions, to pull back names of members in the hierarchy despite the end user not having any access to some members.

Content (please ensure you mask any confidential information):

I am using FlexibleDataGridBuilder, with 'false' as the parameter for building the grid with user security. I build a grid using admin dimensional security, but within a business rule kicked off by an end user running on save.

To help facilitate this I would take the end user's Cost Centre variable, find it's ancestors (using getEvaluatedMembers function), but to run this with admin permissions so that I can access all the ancestors even if the end user does not have access.