SSAS Tabular - USERNAME() filtering

I have a Power BI file and I want to limit the drop down slicer filter to only options that a specific user name has available. I set up a security table and everything for RLS on the SSAS model...and it works great, with the exception of some "comparison measures". To make a reference we have a few measures that are aggregated at different levels (EX: All Sales vs Region Sales, etc.) 

And when RLS security is implemented those measures all appear the same because it (correctly) filters down to only rows that user has access for, making the aggregates exactly the same for the comparisons.

Is there any way to just filter the slicer by where an attribute on the user security table=USERNAME() within the power BI file?

Thanks!