By EE, I meant my Express Entry profile. I did not add those 1.5 years in my Express Entry profile because I did not want to get points for that. I just though it might cause issues later on for FSW as I am only claiming points for 1 year work experience.
Company A: 6 months (Can't get proper reference letter)
Company B: 1 year (Can't get proper reference letter)
Company C: 10 months (Acquired proper reference letter)
Company D: Current since November 2015 (Acquired proper reference letter)
I am only using Company C & D as my work experience. However I added all of my work experience(Company A, B, C, D) in the Personal and Work History in the OINP application form. At this point, I wrote a Letter of Explanation to say that I am not claiming those 1.5 years from Company A & B. But still, I only showed 1 year work experience in my Express Entry profile (Company C & D only).
My work experience summary in different places so far:
Express Entry profile: Company C & D
OINP Application form: Company A, B, C & D
I think it might be better to have less points than claiming more points in Express Entry that cannot be proven with proper reference letters. My worry previously was whether it might be an issue, given that I didn't show all of my work experience in Express Entry. But I took CanadaWeCome's advice to add everything in my OINP Personal and Work History and then send a Letter of Explanation that I am not claiming points for Company A & B.