Your source has no credibility; I have never seen anything that indicates the Smithsonian is engaged in a cover up that destroyed remains of gigantic people. The story of red-haired giants should not be regarded as a hoax: it is Northern Paiute oral tradition that discusses an indigenous population they encountered when they arrived in the Great Basin. No archaeological evidence verifies that there were red haired giants, but one cannot call the tradition a hoax. It is a tradition.

In addition, Lovelock Cave is not in Wisconsin: it is in Nevada. It is not necessarily the location indicated by Paiute tradition.

edit: thanks to /u/Bernardito for identifying the site as satirical. I recognized it as BS; I didn't realize it was intentional BS.

I'm out of the loop here, can you tell me what Red Haired Giants are?