From the documentation, your options to have multiple page listed on a single behavior seems to be limited…

However, you could use a Lambda@edge attached to the default behavior on the origin request and update your origin from your path value.

Another option would be to use CloudFront KeyValueStore and a CloudFront Function. If you’re able to migrate to this approach, you will be able to add any routes easily in the store without having to modify/redeploy CloudFront with each new path.