Use shared API Gateway with serverless-aws-documentation

I have a project that is splitted into two services. The first service creates and defines an API gateway, whereas the latter one just uses it. I’ve followed the documentation here.

Service1 (creates the API Gateway)

frameworkVersion: "^1.26.0"

service: my-first-service

provider:
  name: aws
  runtime: nodejs6.10
   
functions:
  initDb:
    handler: handler.get_initDatabase
    events:
      - http:
          method: get
          path: init-database
          authorizer: aws_iam

Service2 (uses the API Gateway)

plugins:
  - serverless-plugin-typescript
  - serverless-reqvalidator-plugin
  - serverless-aws-documentation # <----- this seems to cause the problem
  - serverless-offline

frameworkVersion: "^1.26.0"

service: my-second-service

provider:
  name: aws
  runtime: nodejs6.10
  memorySize: 128  apiGateway:
    restApiId: ${env:REST_API_ID}
    restApiRootResourceId: ${env:REST_API_ROOT_RESOURCE_ID}

functions:
....
custom:
  documentation:
    ....

When I try to deploy Service2, the deployment fails with The CloudFormation template is invalid: Template format error: Unresolved resource dependencies [ApiGatewayRestApi] in the Resources block of the template. As soon as I comment out the serverless-aws-documentation plugin it works.
Is this a plugin related problem?

Edit: I’ve also created an issue in their repo https://github.com/9cookies/serverless-aws-documentation/issues/72