The Indomitable Lions must claim victory over Germany by a two-goal margin on Sunday in Sochi to progress after taking a solitary point from their first two Group B matches.
Broos' opposite number Joachim Low left a number of star names, including Toni Kroos, Mesut Ozil and Thomas Muller, at home so he could use the tournament to blood fresh talent and Die Mannschaft's next generation have stepped up impressively in a 3-2 win over Australia that was followed by a 1-1 draw with Copa America holders Chile.
"I thought it [would help Cameroon] before the tournament because I saw it was different players than normal," Broos told a pre-match news conference at Fisht Stadium when assessing the Germany squad.
"But after the two games of Germany, I have to change [my view] a little bit. The B team is also a very good team.
"We will have to be on our highest level. It's not enough to beat them. We have to beat them with two goals difference.
"With football, everything is possible. We will go for it from the first minute and see after 90 minutes where we arrive."
Despite failing to get a win on the board, Cameroon's committed and industrious displays in Russia have won approval from local fans in Moscow and St Petersburg.
However, they head to Sochi after the city was forced to confront embarrassing and offensive images of people in Cameroon shirts wearing blackface and carrying bananas as part of a summer parade.
Broos condemned the scenes but appeared keen to draw a line under the issue,
"First of all, I think that it is not up to us to answer this type of question and, secondly, of course, everywhere in the world, if we feel there is racism, of course we are against it," he said.
"So, from that point of view, I think everyone agrees those things should not be part of football."