If there is a tentative site I would recommend Slovakia pushing for nomination, it would be the Chatam Sofer memorial, which for me combines several reasons of outstanding value: not only is it an important pilgrimage place for many Jews as it is a place where Moshe Sofer is burried - he was a very important Orthodox Rabbi and a founder of Bratislava's yeshiva that was moved to Jerusalem after WWII.
The Memorial is also a testament to preservation of an Old Jewish Cemetery despite efforts to destroy it completely. The area around the Bratislava Castle historically was a place where Jews could settle. However, in 1940s and afterwards new town planning projects were drawn - one constructed the bridge across river Danube (the one with the flying saucer) which caused a large part of the Old Jewish town to be demolished to make space for the access road to the bridge. Another "great" idea was to remove the Jewish cemetery to make space for a tunnel. The local community was somehow able to convince the authorities to at lease preserve a section of 23 most important tombs (including one of Chatam Sofer) - it was enclosed in concrete, below the surface of the new road. It was accessible, with a torchlight and the ceiling was very low. It is a mystery how this was done; there are many explanations including superstition or bribes.
In 2002 the site was opened and restored, with the original graves still remaining underground and the top of the memorial was converted to a glass replicas of Jewish gravestones, with their bottoms actually reaching down to the room where the original tombs are - through the ceiling. It was a work of the architect Martin Kvasnica.
The surrounding area is very much urban, but the memorial is visible from the road. The trams stop nearby and the stop is actually called Chatam Sofer. Google their website and book your tour in advance. We visited on a whim when walking around: there was a group of Orthodox Jewish pilgrims, so we were only able to see the graves from the viewing platform behind the glass as to not disturb them while they prayed, but as they did, the local Jewish caretaker actually told us the extensive history of the site, shown us many historic pictures and explained everything. He was very nice and extremely informative. I can't remember if there is an entrance fee, I think we paid some symbolic amount. As I said before, I really hope this place out of all our tentative nominations would get inscribed as I see historical and cultural importance in it, as well as efforts to preserve an important part of Slovak Jewish heritage.