In some languages it might be more natural to reorder this. Alternate translation: "But because of the crowd of people, they could not find a way to bring the man inside. So"
It is clear that the reason they could not enter was that the crowd was so large that there was no room for them. (See: [[rc://en/ta/man/translate/figs-ellipsis]])
Houses had flat roofs, and some houses had a ladder or staircase outside to make it easy to go up there. This can be stated. Alternate translation: "they went up to the flat roof of the house" (See: [[rc://en/ta/man/translate/figs-explicit]])