The vector version is embedded into the two xerox alto disk packs for the 'spruce' imager for Dover or Sequoia printers. Spruce is effectively a partially-software raster renderer (using an Orbit add-on set of cards for the Alto) for very early laser printers. Some later Xerox laser printers may have had the vector font data loaded directly onto the printer itself, so didn't need a dedicated network-linked alto to directly render it. The actual source files for these embedded fonts I'm not entirely sure where to find, but may exist on the "Indigo" xerox alto archives at the computer history museum, which is accessible online.

Here's an example of the vector font version of Cream, rasterized by spruce running on a networked xerox alto using the 'ContrAlto' emulator. This font was usually used by Smalltalk-76 or Smalltalk-80 programs on the Xerox Alto, and printouts of said programs.

The unusual shape of the s, S and B glyphs (and some others) appears to be intentional (as it is consistent between the raster and vector versions of the font), perhaps to make characters less ambiguous on printouts and on-screen on the Alto

The .al font format is described (as a BCPL struct) in the very same pdf file you linked. I have a chunk of c code I wrote back in 2019 which will display the characters to screen from any .al file, although interestingly even xerox screwed up a few of the font headers and character widths, requiring some manual heuristics to make them display properly by the viewer. (these might rely on undefined behavior of the xerox alto microcode to display properly!)