AWS EMR HBase cluster creation - application provisioning timed out

Hello,
I use terraform to create an HBase cluster in AWS.
When I use these settings, I am most of the time successful:

resource "aws_emr_cluster" "hbase" {
  name          = "hbase"
  release_label = "emr-6.3.1"
  applications  = ["HBase"]


  termination_protection            = false
  keep_job_flow_alive_when_no_steps = true

  ec2_attributes {
    key_name  = <removed>
    subnet_id = <removed>
    
   instance_profile = aws_iam_instance_profile.emr_profile.arn
  }

  master_instance_group {
    instance_type  = "m1.medium"
    instance_count = "1"
  }

  core_instance_group {
    instance_type  = "m1.medium"
    instance_count = 4

    ebs_config {
      size                 = "20"
      type                 = "gp2"
      volumes_per_instance = 1
    }
  }

  ebs_root_volume_size = 10

As soon as I increase the number of master nodes to three, the cluster creation fails with the error message:

Error: Error waiting for EMR Cluster state to be “WAITING” or “RUNNING”: TERMINATING: BOOTSTRAP_FAILURE: On the master instance (i-), application provisioning timed out

I checked the documentation for aws_emr_cluster, but could not find anything to set a timeout.

I also checked the timeout settings for IAM roles, but the default setting is one hour which would be absolutely sufficient.
https://docs.aws.amazon.com/en_en/IAM/latest/UserGuide/id_roles_use.html

I get the above mentioned error message every time cluster creation takes longer than about 16 minutes (16 minutes and 20 seconds to be exact).

I also create an AWS MSK resource in the same project, which took longer than 17 minutes. This finished successfully without complaining. So it does not seem like it is a global timeout value.

Any ideas would be much appreciated.

Best,
Denny