ANY keyword not working in release

I've got an interesting problem with DF. I have two tables that I'm querying and get different results just changing the Debug Info for the project. When Debug Info is set to full, it works as I would expect. When set to pdb-only or none, it doesn't work unless I add an extra line. 
Statement looks something like:

var result = manager.Employees.Where(employee => employee.Foreman.Any(foreman => foreman.LocationID == locationID)).ToList();

Employee is a list of employees.
Foreman is a list of employees that are foremen.
So I'm trying to get back a list of employees that are foremen.

To make this work without full debug info, I have to add a method.

var result = manager.Employees.Where(employee => employee.Foreman.Any(foreman => foreman.LocationID == locationID)).Select(employee => employee).ToList();

First example returns x records in debug and zero records (no error, just no results) in no debug. Second example works in both. Problem is trying to remember to add what I would think should be a needless method to the query all over the code unless I don't understand what's happening.

Can you confirm if this is a bug or am I doing something wrong?
Thanks,
Scott