You sorta nonchalantly toss around "the military stepping in." Do you know how friggin' dangerous that would actually be?
If it actually "stepped in," think of what that would mean. First, it would be acting under no legal or constitutional authority at all. In other words, it would be acting arbitrarily and completely untethered from the rule of law. Basically, the Constitution would be completely out the window. Second, it would be acting against what the law says is its commander in chief. That would mean the end of the civilian command of the military. The true commander in chief would be whatever general or admiral that the military was listening to at any given time. That's how the military is run in places like Liberia or Bangladesh, not civilized nations like the United States, but considering that the US military is the most powerful institution in the history of humanity and can literally kill every man, woman, and child in existence, that would be pretty scary - much scarier than if Joe Biden had actually scored a one-off election theft.