Skill trained Vollems are still useful for protecting harvesters like Miners, LJers or Fishermen. My prospector (Mining+LJ+Fishing) char uses a skill trained Vollem along with a skill trained Fire Beetle and Giant Beetle while harvesting. Fishing in the ocean and a Sea Serpent or Water Ele shows up? Vollem kills it. Mining for sand in Compassion Desert and a Orc, Sand Vortex or Scorpion attacks? Vollem kills it. Mining/LJing in the wilds and an Ogre, Ettin, Gargoyle, or Reaper attacks? Vollem kills it. Fishing in Destard and Water Eles attack? Vollem kills them.
Not to mention, if you're careful with where you put the points, you can level up a Vollem once with the advanced Training system, and they'll still require no Taming/Lore to control, so you can take the Taming/Lore off. Corpse uses a 120 Disco Vollem on his Sampire to debuff his opponents.
First thing i'd do, is train it's Resist skill to GM on Spectral Spellbinders in New Haven. Gather a bunch of Spellbinders to spam spells on it, and once it's Resist hits GM, it's DEX should skyrocket up to 125, which makes training Wrest/Tact/Anat a lot easier.
You can train Wrest/Tact up to 50s/60s on Gregorio, a red Brigand near the Ranger Huts outside of Skara Brae. He's immune to pet damage. Once Wrest/Tact is in the 60s, train it against a Shadow Ore Ele with 80s Wrest/Tact as something else tanks it.
Gregorio is the best thing to train Anatomy on, especially if he's disarmed.
Gregorio is also the best thing to train most magic skills on. You can stand in the doorway of the farmhouse, with your Vollem on one side and Gregorio on the other, and have your Vollem attack Gregorio. So long as your Vollem can't physically reach Gregorio, he'll rapidly spam spells on him. Or you could disarm Gregorio, then attack him so you're tanking him, and have your Vollem stand some distance away and say "All Kill" immediately followed by "All Stay", which will get him to keep his distance while spamming spells.