Most of the Isabelle documentation I see says that Proof-General supports Isabelle, but as far as I know PG dropped support about 5 years ago.
Is there another possibility to use (current) Isabelle with Emacs? Neither JEdit, nor VSCode really work for me.
There is no official solution and no way to make Proof General work again.
However, there is an unofficial solution. You could try isabelle-emacs (Disclaimer: I develop it in my free time. The experience is a bit rough, but there are a few people using it). It uses the Isabelle's LSP server like VScode, but it uses Emacs based. The difference between isabelle-emacs and Isabelle is limited to a few line in the LSP server and the Emacs specific code. Neither kernel nor any other theory is changed.