Of course, in English you say "the better team" There is no problem with this, it is not rare and is grammatically correct.
The investors are looking for the better team to support as the previous one has failed their expectations.
"the" in English can be used widely, and here you can use as an emphasis on that particular new team. Not just "a better team" or "the best team"
Better is correct in English when comparing only two items, best is used for the superlative - the best of more than two items. Good, better, best. English speakers incorrectly say something is the best of two items, but languages evolve and maybe someday we'll all have dropped the comparative out of laziness.