Please note that you are following a guide to configure the load balancer in AWS and the instructions for Google may differ.
As the guide mentions, you need to include those lines before the WP_HOME and WP_SITEURL definitions, can you confirm that you added them there?
In order to obtain the log information, we have a Support Tool that will gather relevant information for us to get it. Could you please download and execute it on the machine where the stack is running by following the steps described in the guide below?
How to Run the Bitnami Support Tool
Please note that you need to paste the code outputted by the tool in your reply.