I'm just returned from the mission. Turns out it was some weirdo French Madame who operated a maison close (a brothel), and offered me love romps in exchange for my help in keeping the French monarchy in power. I refused because she and her workers weren't at all appealing. Yuck. Plus, we Americans had our revolution. Would have felt weird getting rid of one from another country. I didn't change any Cowboy games. Pffft! This was back in the 18th century. I didn't have to kill anyone, though I did have to chloroform some jerk to get access back to my time machine.
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So, all of those Super Bowls should be in tact. I'll google them real quick, just to be sure ..... hey, wait a minute! Where are our trophies for Super Bowls 15, 16, and 17? And where's our star D-lineman, Piérre Aisselles Puantes-répugnantes, the one Landry coaxed out of his weight-lifting/boxing career in France? With him destroying defenses, Landry's Cowboys became the only team to win three straight Super Bowls, and the only one to make an opposing NFCC quarterback retire immediately after the game. After Puantes -Répugnantes sacked Joe Montana 13 times in our 54 to 6 victory in the '81 NFCC, Montana proclaimed, "I'm just not cut out for this game," and quit.
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That dirtbag I chloroformed must have been Puantes -Répugnantes' Great Great Great Great Grandfather, and maybe the chloroform sterilized or killed him. Aw, crap. I'm sorry for ruining those three Super Bowls. I'm going to go back and fix this ...... hey, wait a minute. Where did these Super Bowls 27, 28, and 30 come from? We didn't win those. After Landry retired in 1990, our new owner, Dan Snyder, hired Richie Kotite, and we only won 6 games in all of the 90s and 2000s (all six against Washington). WTH????
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Whelp, it's three for three. Do you want me to go back and restore the team to having won Super Bowls 15, 16, and 17, but not have any of our 90s-era Super Bowls? Or should I just leave it the way it is?
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Oh, and Dan Snyder was an AWFUL owner. He relented under public pressure to change the name of the team from the "Cowboys" to the "Nice Guys" and he replaced the star logo on the helmet to a picture of Dudley Doright. I sure hope no other team is stupid enough to hire Snyder in this other timeline. There may be some hope, though. Roger Staubach is our new team owner, at least he was in the other timeline.