Azure OpenAI is not the same as paying OpenAI directly. While you may not be able to pay OpenAI for them to run models in Australia, you can pay Azure: https://azure.microsoft.com/en-au/pricing/details/azure-open...
The models are licensed to Microsoft, and you pay them for the inference.
There is no way to upload files as a part of context with Azure deployments, you have to use the OAI API [0], and without having an architecture diagram of the solution, I am not going to trust it based off of the known native limitations with Azure's OAI implementation.
[0] https://github.com/openai/openai-python/issues/2300