Approver Comments:
It looks like Jakub Jerzy Orbach survived the Holocaust. The Pinkas HaNitzolim I data appears to be a positive ID -- same name, birth date, and birth place. Also, if you cross-reference the World Jewish Congress names for Jakub's mother (Bracha) with the Lodz Ghetto Database, you find a woman named Brucha (born 1887) who lived at all three of the same addresses as Jakub. [Menachem, however, is not with them.]
Also, both Pinkaz HaNitzolim I and Sharit Ha Pletah list a man named Jerzy Orbach from Lodz, born in 1924, who was liberated at Dora (Nordhausen). Until October 1944, Dora was a subcamp of Buchenwald. Therefore, it is possible - given a birth year variation of only one year - that the Jerzy liberated at Dora (Nordhausen) may be the same one listed as liberated at Buchenwald.
Also, please make note of the following spellings for Jakub Jerzy Orbach's name:
World Jewish Congress - Jersy Orbech (born 1925 Lodz), Jecb Aurbach (born 1925 Poland), Jakub Orbach (born 1925 Lodz).
Pinkas HaNitzolim II - Jerzy Urbach (Lodz) and Jakub Urbach (Lodz)
Pinkas HaNitzolim I - Jerzy Orbach (born 1925 Lodz) and Jerzy Orbach (born 1924 Lodz)
Sharit Ha Pletah - Jerzy Orbach (born 1924 Lodz)
Finally, I'd love it if you double-checked on a hunch for me. A number of Lodz Jews were sent to forced labor in the region of Czestochowa in May 1944 and from there survivors were evacuated to Buchenwald (among other camps). Please go back to Stage 3 (Labor Camps) and double-check whether Jakub Jerzy Orbach was sent to Czestochowa. If he was, you can find out more about the camp (and Jerzy's experience) in the Secondary Sources under "Forced Labor Camps."