While the Cowboys can still win the division if they win one more game than the Eagles the rest of the way .. in other words, the Eagles have to lose, the reality is that when the Cowboys lost to the Cardinals AND Eagles (in their first game), they handed control of the division to the Eagles, who still have it.
The home winning streak is great, but those kinds of records can motivate opponents in the playoffs, so even if the Cowboys play at home in the playoffs it does not mean they will win those games.
The best thing the Cowboys can do is focus on winning their remaining road games to prepare them for their "road games" path to the Super Bowl.
If it happens that the Cowboys end up winning the division, that would be great, but they do not control that so better to focus on what they can control.
On the bright side, no NFC East team has repeated as division winners since 2004 .. of course it was the Eagles who last did it.