Buying peanut butter from a company that cuts down rainforest is evil, but the evil can be excusable if it had a sticker on it saying it was rainforest-friendly.
It's not excusable if it had no such sticker and you're ignorant only because you failed to do research. If it didn't work this way, terrorists could not be considered evil as they thought they were doing good, despite being able to know that what they were doing was evil.
By this standard not doing your research on everything you purchase or barter for allows you to be evil(that can't be excused) and that good people must always strive to be informed and do so successfully to not be committing evil.
Also the underlined supposes that all (or that it is just a general rule that) terrorists aren't caught in mental feedback loops that their previous condition/state negates the possibility of without outside intervention. IE depression leading to suicide
This is a bit more nuanced because of the multiple different factors (if it had no sticker, it was still environmentally-friendly, but then it stopped being without your knowledge, it's fine), but this is the basic idea.
It is quite a complicated basic idea then, with a lot of moving invisible parts.
Greater good is simple. Kill one innocent person to save a hundred innocent people. You're committing an evil by killing the one person, but you're committing a great good by saving a hundred. Committing the evil was necessary to performing the greater good and so it can be excused. (Just an example. Does not necessarily reflect my views.)
This is one such part.
Innocence
2. not responsible for or directly involved in an event yet suffering its consequences.
Because you must conclusively argue that every one of those people is not directly involved in this event and have definite criteria to prove their collective individual actions have not given rise to a situation where this result will deterministically happen.
Natural global warming being exacerbated by "pollution" is one such situation where many independent actions lead to a situation that will deterministically happen, which I'm assuming is part of your environmentally friendly bit.
And the reason you must conclusively argue that those people are not directly involved in this event is because you explicitly state that ignorance isn't an excuse if you could have taken an action that could end such ignorance. This fails to take into account 'how and why' you come to the conclusion that you need to end such ignorance in the first place and how you know whether it is impossible to know or not. And as a consequence of this you must also prove it was impossible to know or not.