We know from the Atom E’ve special that she had a mental block against using her powers on living tissue. The Eve from that universe now has basically nothing but her mind and nothing but time, so that if she really wanted to she could get to work on overcoming that mental block, heal her spine with her powers, and then… I don’t think Viltrumites would be any more resistant to her powers than anything else, if she could use them on living tissue.