ECC is the answer. There may also be a special tunable you can turn on that causes ZFS to do extra checking in memory, but it can't provide guarantees.
Yeah, and if I lived in the US I'd use it, along with the right mobo. But as things stand, such tech is only sold by B2B outfits at B2B prices. They don't even have a door I could walk into!
Did you run a scrub after you removed the bad RAM, and still have errors? If so, then you know the pool was really damaged. If not, it is possible you had no stored damage and the errors were happening in real-time only.
I couldn't run a scrub by then, because I couldn't unencrypt the zpool -- trying to do so caused an instant reboot every time.
As for the scrub of death, it can't exist. The worst is what may have happened here: corruption in RAM of the metadata that becomes a permanent part of the pool.
Never heard of the scrub of death. Sounds like a rusty steel wool loofah!