Hello,
really interesting question, thanks for that! Overall, the analysis that you've performed is very good in my opinion, congratulations. :-) Answering your questions:
1. I think yes, it should work without any special configuration, but that would depend on the prompts that you're going to input - how complex are they etc. Basically when you define Dataverse as a datasource for the bot, it probably uses ODATA query to grab the data and then generate a response based on the data retrieved. You should keep that in mind when prompting - the prompt should be constructed so that the model could understand to which columns it is referencing. You'd probably also need to manipulate the system prompt to achieve desired results.
2. You'd need to test as it mainly depends on the datasource that you're connected to. The best way to check is to create a sample table and see how it performs. It's a new technology, so everyone are testing - it's not possible to give unambiguous answer for now. :-)
3. It should, keep in mind though that a lot is changing on the platform and giving you 100% certainty is impossible.
4. I'd go with Power Platform/Copilot Studio environment as the task is possible within existing low-code environment. I'd avoid Azure as you'd need to perform a more complex setup to prepare the solution.
Overall, the deadlines are too tight given the fact that the products are new and a lot is changing day-by-day. The expectations from the business to prepare a fully functional product, based on not fully stable environment, is not a good approach. I understand though that the pressure is big now.
The choice that you'll make also depends on the data quality. If it's poor, then you'd need to work with the business to prepare a more reliable dataset.
To sum it up, I'd try to prepare MVP by myself and see how it performs. Your lack of coding experience is not a problem as you're going to use low-code solutions. Lack of knowledge about SQL could be a problem in database design, but what helps you is the low-code approach in Dataverse. Then, after you prepare an MVP, you could decide if you'll manage to prepare a fully functional product or if it's better to transfer it to the external party. That's how I'd see it.
In case of any other questions, let me know. If the answer helped you, mark it, so that others can benefit from it.
Best regards,
Artur Stepniak