No, I didn't because this is a project that I can't pursue. But the usual situation in academia (and, I guess, anything that is not self-published) is that the copyright owners of publications are not even the scientific institutions that produce those materials, much less the researchers themselves.
People who are interested on the subject and who may want to pursue a project like this one are likely to be academics or ex-academics, and they know beforehand that it's not just the technical work they need to put on, but also everything connected to matters of intellectual property involving multiple parties. That knowledge is enough to discourage most.
> I didn't because this is a project that I can't pursue.
Okay. No worries. I don't have time for it either. :)
> That knowledge is enough to discourage most.
I see that you are discouraged. I say this in the kindest way possible: have you considered that maybe the barriers you perceive are only there in your own mind?
> the copyright owners of publications are not even the scientific institutions that produce those materials
"COPYRIGHT UNDER THE INTERNATIONAL COPYRIGHT UNION, 1959 ALL RIGHTS RESERVED by THE ORIENTAL INSTITUTE, CHICAGO, ILLINOIS" is what the dictionary itself says.
These are the people behind the "The Electronic Publications Initiative of the Institute for the Study of Ancient Cultures"[1]. (as I learned by clicking the "terms of use" button next to the download links of the dictionary.) Based on that it seems they wouldn't want you to host the files on your own site, and they don't want you to sell copies of their books, or profit from it in other ways but you could very likely just make the search system which refers people to the right page of their dictionary without copying their actual entries. That seems to be fair play both legally and on an emotional level. If you want a more integrated search experience that is where reaching out to them and hosting it on their own site could work.
I know nothing about assyriology and copyright things can indeed suck, but these people in particular seem to be good eggs. It is possible that secretly they are copyright Scrooge McDuck about their dictionary but if so they are going very weirdly about it.
People who are interested on the subject and who may want to pursue a project like this one are likely to be academics or ex-academics, and they know beforehand that it's not just the technical work they need to put on, but also everything connected to matters of intellectual property involving multiple parties. That knowledge is enough to discourage most.