A BOM would be lovely and glad that you include a link right on the board, but isn't a showstopper - most components are fairly obvious on inspection/testing (not so much when manufacturers sand off/exclude/obscure IC identifiers), but a list would definitely be a huge timesaver. A schematic is almost essential though - I think the PolyEvolver board is 6 layers and would take ages to map out.

Oddly enough, someone else mentioned the other day that Sequential started a cloud-based service for converting wavetables to a usable format for the new Pro3 [0] - it's free now, but maybe a service after DSI was bought out by Focusrite?

As for source code, updates are still downloadable from DSI, plus the microcontroller has an I2C or JTAG interface and isn't protected AFAIK; wouldn't be overly difficult to extract the source (albeit in machine code). I think I previously ordered backups of the DSP and microcontroller when they were still available - just in case, but there are a bunch of components that aren't available from DSI or supply shops anymore (e.g., the custom CEM chips). I think that's an aspect of the right to repair that may be overlooked - component availability.

[0]: https://www.sequentialwaves.com/