embyforyou
arun@crackverbalA doubt here - I understand that it is not materialized yet but why can we not say with future certainty that "the researchers will have to know XYZ to understand ABC"?
I won't comment on "would have to know" and "will have to know" (your main question).
I just want to share my opinion about "have to know" and "will have to know".
Normally, we say:
a) You know that I like you.
b) You will know the truth when time comes.
However, when we use "have to" to express an objective obligation (vs. "must" as the subjective obligation), "will have to know" seems a little bit off to me.
For example, if something is objective in the sense that knowing it is good, then the context lends itself to a fact, and the objectivity of "have to" gives it the simple present tense (a fact, a rule, a common way of acting,...)
Ex: To become a good person, you have to know when to stop.
- Weird: To become a good person, you will have to know when to stop.
- Reason: it is a fact which is based on the objectivity in "have to" (i.e. not in my opinion but based on others, or just a rule in life), so you don't use future tense to reflect that fact.
This is my opinion. But the objectivity sense of modal verb "have to" is right

Note that I am discussing the grammar itself, and not the official answer (which I think is ridiculous).