I know this is probably going off at a tangent, but why do we need the source code, to advance the games. surely what we know already could be used for this andd even if they did release the source code it would probably be for WC1 or 2, games that quite frankly could not be advanced enough to make it worthwhile, look at doom legacy, that is basicly just doom with a few limited changes, the graphics engine has not been massively changed, and the same would happen with WC, unless we got the prophecy or SO code, advancement could not be made that would be major, WC3 or 4 could be done, however virtually all the games have an engine equal wc1, 2, academy and privateer
wc3,4,armada,privateer2
wcp,SO
admittedly these engines are not exactly the same but they are similar enough, therefore if all the editors for games of a 'set' were compiled, then enough information could be gathered to give us a reasonable, if basic knowledge of the code, unfortunately most of the people who made this software have moved on such as HCL,
Basically to make any changes we need a grasp of the code, but not a massive one, and if enough people banded together such a grasp could be gathered, look at all the patches (dehacks) made for doom prior to source code release. admittedly they had 5 years to get this grasp, but with no WC future likely we could have that long, such a project would be hard and for a long time completely fruitless, but if in the end we have a decent wc4 code or even a wcp code, then we would truly be able to advance.