Making a mistake with this false friend could have serious consequences! But in German, those consequences would be “schwerwiegende/ernsthafte Folgen”. So serious means “ernsthaft”. The German word “seriös” means something different. A “seriöses Unternehmen” is a reputable/respectable company, so the word suggest reliability and trustworthiness.

So “Die Leidenschaft und das Engagement unseres Teams…” would be “Our team’s passion and commitment…” The English word “engagement” is different. It normally means “Verlobung”. In some contexts it can mean other things like “Einsatz”, but generally with a sense of involvement rather than commitment.