The NIT tournament actually started just a year earlier than the NCAA tournament (1938 v. 1939), Pap, so it's not really accurate to call it "well established."
The AP poll did not start until the 1948-9 season and the coaches' poll after that, so they're not useful in this case.
None of the retroactive championship selectors, such as the one in ESPN's college basketball encyclopedia, have ever named our 1942 squad as champions to the best of my knowledge. Looking at our 19-4 mark compared to NCAA champ Stanford's 28-4 record, I can't say I blame them.
There's nothing stopping the school from claiming it, as you say, but with no empirical support it would ring more hollow than Pitt's leather-helmet football titles that everyone here is so fond of deriding.
No, I think we're better off standing proudly on the 1959 runner-up status as our basketball apex for the time being. For perhaps the first time in ages, it's not so ridiculous to suggest WVU hoops has at least a viable chance of surpassing that previous height in the near future.