You've not provided any evidence from the university outlining his substandard performance. In any case what did the opposition hope to achieve except something counter to academic freedom?
Your other questions are red herring.
Here, but you'll need a subscription. It gives him high marks in publishing while doing postdoc at UT and UW, "It looks like it slowed down considerably. It’s not clear that he started new things, or anything on his own, in the period he was an assistant professor at Iowa State." The article also states his low grant rate and lack of graduate students completing their work.
In any case what did the opposition hope to achieve except something counter to academic freedom?
For the publications, academic excellence and prestige. For the students, well, students completing their doctoral work is kind of one of the reasons the school exists. For research grants, schools rely on those for income, plus big grants are likely to produce big results, which brings prestige, which brings more grants... That's how universities work. That's how the tenure system works. If he didn't like it then he shouldn't have been in that line of work.
Your other questions are red herring.
The other questions go straight to the heart. ID proponents are screaming persecution and don't want to see that he was denied tenure for solid academic reasons. It hurts your case. You also can't stand back and look at this rationally to see how this is just like a liberal playing the race card. It looks like IDers would like ID proponents to be a protected class, and I hate protected classes.