Using Google Image sometimes helps you when you encounter unnatural translations. As @8enP1jip told us, "palang" + "jalan" mean "boom gate" that can be also set in a parking lot, "railroad crossing gate" or sometimes "barricade" set between agitated demonstrators and police. "Palang Merah Indonesia" (PMI) means the Indonesian Chapter of the International Federation of Red Cross.
As of Feb 2021, the default translation is still "There is no road after this cross." I saw unfixed translations more frequently than in the early stage of the course. I guess many people dropped out and fewer people reported issues after the 3rd checkpoint.
I believe @glhaynes90's suggestion is quite accurate and should be considered as the default translation by the course developers.