There are two healing chambers in General Raze's headquarters, which can be temporarily deactivated by throwing a lever by each of them. In the original release of D2:ED you could block his path to one or both of the chambers by summoning your creature and letting his summoned walking armours build up. If he couldn't get to the nearest healing chamber he would run for the far one, giving you additional time to do enough damage to finish him off.
In DKS I think you pretty much have to start off by disabling both chambers and then do as much damage as possible before they come back online. General Raze can teleport to the healing chambers if his path is blocked (or you are in the middle of a Thousand Strikes attack on him), and can run there even if he is under the effect of a Stun Arrow, etc.

There are more malachite gems in FoV than D2:ED, available randomly from veins and as quest rewards. I reloaded at veins to get 2 or 3 gems from each and reloaded when turning in FoV quests (that gave multiple quest rewards) up to 3 or 4 times to see if I could get malachite gems (minor and side quests could have a set of 2 random gems, while main plot quests could have 5). At the end of the Hall of Echoes I had 23 malachite gems (I used 2 earlier for healing aura enchantments, and gave 2 to the blind philosopher); at the end of FoV I had 65 malachite gems.

Your runners will never be able to fetch malachite gems (one can get malachite ore, but there is no way to refine or convert the ore to gems).