You could use Dev Containers from a selfhosted or cloud based service to circumvent the logistics with local OS/VM setup:
If you need better bandwidth/latency for visualizations than your network can provide, then you could install something like docker desktop on local hardware, that is: if you have the time to walk students through a docker desktop install, and that students have enough local compute power to run your software stack.
Is that a static point cloud, is it colorized with a certain bit depth, or does that have some kind of update rate? I’d recommend doing some napkin math on what kind of bandwidth you’d need as a base line if you wanted to send them over the wire and render them from something like Foxglove Studio instead. For example, it may be worth down sampling point clouds remotely before visualizing them over a local client, or sticking with your current approach using remote desktop or VNC to render the visualizations on the same remote compute instance, then stream the frame buffer of something liked rviz instead.
Something like Moonlight and Sunshine could provide a more responsive, while still FOSS, remote desktop experience, but would be a more involved setup compared to a conventional VNC server/client deployment.