When third party implement your API into its website, it can accept other cryptocurrency or just your coin ? Also there is team member? I don't companies will ignore other service that have team and use service with anonymous team.
They can accept only our coin. About team please see the image below

If you allow only your coin, what will make those website implement your API instead of using other service that allow them to accept different cryptocurrency? what do you provide to encourage them to use your service?