The names are similar, but they're by no means the same.
Literal
Name [topic-は] resemble [progressive-ているが], they [topic-は] absolutely same [copula-ではない].
決して ('never, by no means') + negative = emphatic negation, 'absolutely not X.' 似ている is the state form of 似る ('to resemble'). Classic Japanese distinction: resemblance vs identity.