A fair point, I just don't seem to remember them leaking goals all over the place, most weeks they seemed solid enough - 15 goals against of those came in 3 games but yes you are statistically correct.
The run of 2 goals scored between December and April was what effectively relegated them.
I watch quite a bit of Bundesliga and went to the Borussia Monchengladbach - Paderborn game last season. Paderborn lost 2-0 away at Gladbach (who went on to finish 3rd) and looked pretty solid if a little blunt up top.
Paderborn finished bottom but Hunemeier was the stand out defender...