The "base" directory of the Japanese localization of Bejeweled 3 from Zoo has plugins to handle advertising in the game, with most symbol files for the proprietary framework/engine, netcode for connecting to Zoo's (or some JP site idk) servers and a small amount from EVEN the game, obviously since they're not executables, you can't run them. This internal framework seems to one of the closest to PVZ2 or a custom version as formats like RSB were being development which aren't in any other PC PopCap game aside from this one or Bejeweled Blitz on Windows 8.

pl.dll: Seems to be a plugin related to loading the game. Despite what it sounds like, the associated PDB and compiled libaries do NOT match this file, it is still provided however.
pl_d.dll: Unknown what the _d means as both are Debug, a matching PDB and compiled libraries are provided.

-LHR