You don't like him, I get that. And you're correct, he is not much of a rim protector, especially if you measure that protection by blocked shots. But I don't know how you can support your contention that he is a poor rebounder. You can argue he is not a great rebounder and insist we should be prioritizing that skill when we draft but the stats and the situation indicate he is far from being poor at it.
For one thing, as a Wildcat, there were fewer rebounds than typically available due to pace. They scored 76.6 points per game and held their opponents to 65.9 points per game. Lauri averaged 30.8 minutes per game and pulled down 7.2 boards per. That's a pretty fair average, even for a center.
His numbers are fine just considering pace but they start to look much better when you consider he spent most of his time on the perimeter, whether because he was playing the small forward position or the fact he was stationed there on offense even when he played the power forward and center spot.
Despite spending so much of his time on the perimeter, he even led his team in offensive rebounding percentage and narrowly missed leading his team in defensive rebounding percentage too. He blocks out and he rebounds his position well IMO. He doesn't go sky high for boards or steal a lot from the other team but he typically grabs the boards you would want and expect him to. That's not my definition of a "poor rebounder", is it still yours?