She believed that in the event if Biden and Harris failed to be inaugurated on 20th of January she would become acting President as Trump's and Pence's terms expire and she is the first in the line of succession after Pence. But her stolen laptop contains proofs of crimes that make her ineligible to serve as President (like giving aid to enemies of the US as per 14th amendment). So then it would be Grassley or Pompeo who become President in that scenario.