Create a Draft Order with deposit by amount not percentage

I know you can create a draft order and then set a payment term with a deposit amount manually. I need to be able to set the deposit in terms of a fixed $ amount and not a percentage amount. I was trying to achieve this using a graphql and using the DraftOrderUpdate mutation but I can’t figure out how to specify the deposit amount. I also tried to retrieve an existing draft order with a payment plan and a deposit already set but when I use graphql to retrieve this draftorder, I do not see where the deposit is specified.

Where is this information stored in the DraftOrder graphql object? And can I update the draftorder with a different discount amount using graphql?

Yes, I would like some help in trying to find out how to do this.