You’ve borught up the crucial point. You can’t vote absentee unless you request an absentee ballot. I’ll add that the ballots won’t be sent en mass to a few addresses. I’d like to see the absentee voter’s list examined for dead voters.
After you examine the absentee ballot list for dead voters, find out for whom they voted.
What if you find some? Throw out all absentee ballots? That's a plus for the CommiecRATs.
In order to cheat large scale, you would first have to determine who definitely won’t vote. Dead people of course are good candidates. If they are daring, they could include people who have mot voted in a long while.
The next step would include an elaborate network of people willing to let their address be used.
This makes it unlikely.
I do believe it happens small scale...people voting for dead granny of for the kids who are away at college. Hut a large scale effort is nearly impossible.