No but I can confirm that both M.2 slots will work while the internal graphics card is in use. I'm not sure how many PCIe lanes are given to both NVMe slots.
I asked about this a while ago on a different sub before testing it myself:
https://www.reddit.com/r/MiniPCs/comments/1395dyj/how_many_nvmes_can_i_put_in_a_lenevo_thinkcentre/
Stack them sideways and get a patch panel.