Getting impact chronology straight
Greg, among your many errors:-
Hellas and the other great impact basins of Mars and the Moon date to before 3.7 BILLION years ago. The K/T impactor was 65 MILLION. No link.
Also, bacteria are regularly recovered on Earth from igneous rocks buried to great depths. Once a rock has cooled, it is available as living space for any life around.
The escape clause, hoever, is that ejection from Mars requires the rock to be in the uppermost few hundred metres, whilst Mars is frozen to an average depth of 10 km.