After 15yrs As A Waitress, They Want To Rehire Me As A New Employee, Am I Entitled To Any Compensation?

I would like to start this by stating I am asking this on behalf of someone else. They do not have a reddit account and a brand new account cannot post. This is for a waitress in NYC.

I've been working for this restaurant for the past 15 years, originally it was owned by two friends but one of them passed away and another family member bought his part. After being with us for over 5 years this new owner became the sole proprietor of the restaurant and now he wants to rehire us as new employees. I'm very concerned with so many questions. Am I entitled to any compensation for the years I worked, if there's any compensation at all? Is this legal? Should I sign the new contract and forget I spent 15 years for this people and start brand new?

UPDATE: First thank you to all that replied. From the responces already and after posting we were able to get in contact with a friend who is a hiring manager at a different company, our question and concerns have been answered.