Dependency management with either Java or Python is PITA IMO, but my idea would be to avoid dependencies during this initial phase of learning the basics.
On one hand, it seems like an antiquated curriculum. On the other hand, a surprising number of mid-sized companies still run on Rails or Django.
(I don't comment on the usefulness of Rails and Django to small companies and individuals, because they're not the ones hiring bootcamp grads.)
The other thing about Python is that, because it's already so popular for teaching, it has an ecosystem of tools around that. E.g. it has turtle graphics in the standard library (!), which is a very good way to explain loops, recursion etc for visual learners. There's also IDEs like https://thonny.org/ that visualize program execution step-by-step.
With Java you will spend a huge amount of time on pointless ceremony that can seem important to a beginner but is really pedantic enforcement of programming preferences from the Java designers (everything is a class for example).
With Python you have a pretty easy language but the dependency management situation is a disaster. Python in a Google Colab notebook where everything is pre-installed could be good.