When talking about an agreement, the word meant is usually הסכם.
They are two separate things. English has one word for both.
Agreement as in the event of agreeing - הסכמה
Agreement as in a contract which we agreed upon - הסכם
Based on the English, shouldn't either Hebrew word be accepted? It would seem that either "הסכמה הזאת" or "הסכם הזה" would be a correct translation into Hebrew if you didn't have additional context.
Why הזו and not הזאת?
I am quite sure they are interchangeable, according to the course notes
Agreement should be translated as הסכם and not as הסכמה...