First time mortgage with poor credit + co-signer

My husband and I are 30 years old with a child looking to purchase our first home but we have a unique situation … - I am a permanent teacher with a gross salary of 65,000. I have a poor credit score of 557 - My husband has owned his own business for 6 years. He filed his taxes incorrectly for the first few years and ended up owing the CRA a large sum of money. He ended up doing a consumer proposal about a year ago because of this. However, he does really well for himself and makes over 100,000 a year. He has a down payment of 35,000 saved up. - We are trying to get pre approved for a mortgage and have been advised to leave him off of the mortgage so that I can go with an A lender and only pay 5% down payment vs 20% with a B or private lender.

We are waiting to hear back from a mortgage broker but what are the odds I will qualify for a mortgage on my own with my parents as a co signer? Realistically, even though my husband wouldn’t be on the mortgage he is the one who will be making the bulk of the mortgage payments. We need at LEAST $500,000 to afford anything in our area. Feeling hopeless.