We can't deactivate the process or the reactor normally because we have to be in control of the main reactor, which requires:
- Reactor status stable
- Control over a majority(5) of the tiles in the reactor by a single faction
- Control over the central tile by the same faction
Engineers and megas both control 3, so we cannot activate or deactivate processes. Engineers can still use their group action, that is true. However, if one person in there goes missing in action or forgets, then we'll see the major collapse happen. It's safer to use the expanding foam, which requires no group action.