Thanks for all of the helpful posts. This script works with Workflow Manager, and I think that with my current workflow(below), if I used GetCount, I would have to make 2 feature layers. So I'll go with len([r for r in arcpy.da.SearchCursor....])
Workflow
-Use .sde connection file to connect to default version of database.
-Get what should be a unique polygon attribute (but isn't always unique) from WMX for a SQL query.
-Make feature layer of whole feature class without SQL query (The whole feature class is created because the polygon may or may not yet exist in default - rec and posts are scheduled nightly)
-Change version (based on WMX user)
-Create SearchCursor on version, using SQL query to limit records, and get len(SearchCursor) (Here I could create another feature layer using the SQL query, in order to be able to use GetCount. Seems inefficient?)
-Based on number of records in search cursor(>1, 1, or 0), do stuff.