CloudFormation: How to add multiple ARN for condition in a policy

I have an existing event rule and I am trying to add a new event rule to the existing bus,

There is a sqs policy which has allows the condition to allow ARN of existing rule, I am struggling to add arn of new rule

Here is the Cfn code

Note: I have tried to add "[]" but it didn't work, also new eventrule does not exist means it has to be added as new rule.

EventBus Code....
//

ExistingEventRule:
    Type: AWS::Events::Rule
    ...

NewEventRule:
    Type: AWS::Events::Rule
    ....
    
 DlqSqsQueuePolicy:
    Type: AWS::SQS::QueuePolicy
    Properties:
      PolicyDocument:
        Statement:
          - Action: sqs:SendMessage
            Condition:
              ArnEquals:
                aws:SourceArn:
                  Fn::GetAtt:
                    - [
                        ExistingEventRule,
                        NewEventRule,
                      ]
                    - Arn
            Effect: Allow

Error: An error occurred (ValidationError) when calling the CreateChangeSet operation: Template error: every Fn::GetAtt object requires two non-empty parameters, the resource name and the resource attributes

Original syntax

Condition:
              ArnEquals:
                aws:SourceArn:
                  Fn::GetAtt:
                    - NewEventRule
                    - Arn

You have to do it separately:

            Condition:
              ArnEquals:
                aws:SourceArn:
                   - !GetAtt ExistingEventRule.Arn
                   - !GetAtt NewEventRule.Arn