GetModelviewProperties leak memory

[Bullhill]

When using GetModelviewProperties its not clearing the memory after collection of data.
I need to add GC.Collect() and GC.WaitForPendingFinalizers() to get it to clean the memory.
(Pay attention to line 17-18 in code and Process memory on images)

This model have 3 956 555 property values so that can explain the amount of RAM, but not why its leaking.