Since you are seeing "BOOTSTRAP_TIMEOUT" issue in a new workspace, you need to make changes in your AWS network config. If your workspace is configured with customer-managed VPC, then please check if routes are valid, NAT gateway, and IGW are configured correctly as well. To further troubleshoot, you can deploy an EC2 instance in the Databricks data plane subnet and try to reach internet.

https://docs.databricks.com/administration-guide/cloud-configurations/aws/customer-managed-vpc.html