I don't have those particular guns but I use the two part "All Plastics" glues for everything now, including the rubbery plastic. I find I can break the bond if I want to but it doesn't just fall apart by itself.
These are the packs that have a tube of cyanoacrylate super glue and an activator pen containing n-heptane. I think the Loctite product below is the original but there are cheaper brands that are exactly the same stuff (Selleys in Australia).
https://www.loctiteproducts.com/en/products/fix/super-glue/loctite_plasticsbondingsystem.htmlThat rubbery plastic was supposed to be formulated to work with ordinary polysyrene cement but I haven't tried it.