No and no.
I don’t think there are any tools for opening native, proprietary Inventor files outside of Inventer. That would not be how Autodesk “plays the game”.
Your best neutral file format for swapping with Inventor will probably be STEP 214.
Rhino and Inventor do not use the same rendering engine so they do not share a common material definition. I would be surprised if anything about rendering material assignments survived the STEP file transfer.
I do not know if it is sufficient for you, but as you can see on the table at the bottom of the page, it keeps some attributes such as colors, properties and mass properties.
I found out do, that no Rhino cannot import autocad materials, but I can use all
the textures do and create the materials using does combine with Rhino
materials…