In which country are you based - could you get in touch with an accounts manager at AWS or Azure?

https://aws.amazon.com/education/awseducate/

I have worked in the education sector previously, and AWS was flexible to develop a solution for students/younger gen that was at no additional cost to the credit/standard offering... Perhaps this is something you can give it a go with inquires? Otherwise Linode or DO with the credit could be something you manually do with an API through hourly billing...