[SG] bad relationship with past HR

Hello my last work experience was in a small research center in Singapore. I had made good relationships with my team and had a referral letter signed by my direct manager when I left the role. I had bad relationships with the HR person working at this place. Now I moved to the USA.

Are there any systems for background checks used by HR personnel accessible across the globe in which the previous HR person could have inputted bad looking information about me?

Is this system single unique standard or there are many and it is firms dependent?

Would a reference letter from my direct manager be enough evidence to disproof whatever may be written about me on the background checks system used?

Thank you