Yes, I am aware of it. But the Museum of History of City of Gdańsk claims, for example, that they collect various documents via purchases, and sometimes via donations.
In addition, some documents in Gdańsk Archives actually survived the fires.
At the end of 1944, the authorities of Gdansk Archives have taken action to protect the most valuable collections. In March 1945, the Archives building was burned along with the rest of the documents. The records that survived were those moved out of Gdańsk to the estates in the Western Pomerania and Germany and those left in the basement of the administration building. A few months later Dr. Marcin Dragon, a pre-war delegate of the State Archives Department of the Commissariat of the Polish Government in the Free City of Danzig, arrived to Gdansk.
He organized the constant supervision of the survived parts of the building and the archive.
gdansk.ap.gov.pl/o-archiwum
Just in relation to Oliwa's Chronicle the National Archive in Gdańsk contains these:
+ Manuscript of Oliwa's Abbey, sign. 940/420, paper, 54 leaves in quarto
+ Manuscript of Oliwa's Abbey, sign. 940/421, paper, 53 leaves in quarto, previously archived in Königsberg
+ Manuscript of Oliwa's Abbey, sign. 940/422, paper, 88 leaves in quarto. Includes "Annales" 1170-1629, previously in Königsberg
+ Copy in Bibliotheca Archivi, 300, R, LI, q. 55-56, poz. 1. Copy of the Petersburg edition, original in Rumiancew Museum
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BTW, in addition to these four documents in Gdańsk, there are altogether 12 various sources of the Chronicle archived elsewhere:
1. Bibl. Ap. Vatic, Bibl. Chig., Ms Q II 516 3 ;
2. Niedersach. Bibl. Gottingen, Cod. Ms. Theol. 207;
3. Zakład Narodowy im. Ossolińskich we Wrocławiu Rękopis Pawlikowskiego, nr 123.;
4. Universitatsbibliothek Greifswald, Acc. 22156;
5. Staatsbibliothek Berlin, Nachlass Oelrichs, Nr 466;
6. Biblioteka Uniwersytetu Jagiellońskiego w Krakowie, zbiór rękopisów, sygn. przyb. 57/52;
7. Biblioteka P A N w Kórniku, rękopis nr 65;
8. Lwowskaja Naucznaja Biblioteka im. W. Stefanika, Acta privata d. referendarius Lucas, 1820, sygn. 0 4, on. I , N° 636;
9. Linkópings - Stifts - och Landsbiblioteket, sygn. H 3 a;
10. Archiwum Państwowe w Toruniu, Katalog II,sygn. XIII-55;
11. Staatsatsarchiv Greifswald, Rep. 38, f. Hs, Adelung Nr 15;
12. Kunglinga Biblioteket Stockholm, D 1360.