Borneo is an island of Indonesia.
Hitched a bit in the North East, Indonesia part of Kalimantan timur. Paid for a lift on a rangers motorbike 30km down a track to the 'main road' near Kutai national park. First truck passes, stopped at my waved hand, 3 people inside, I became the fourth! From the middle of the jungle to the next big town of Bontang, or was it Sengatta. Anyway, a 30 or 40km trip. I did not speak much Bahasa, sure they spoke no English. I just said Salamaat pagi, tidak rupiah, terima kasih (hello, no money, thank you). they replied Ke mana? Blandi? (Where are you from/What you doing here? Dutch?) I replied Jalan Jalan (just walking). That was it, just make it clear that you have no money at the start, and avoid problems.
Had no problems hitching across Kalimantan from the Tebedu/Entikong (Malaysian boarder) to Sampit in central Kalimantan to get a ferry to Java, I was asked for money once or twice even though I stated before I got in that I would not pay for a lift. Gratis is a handy word and most people understand it. People are very friendly and its quite safe to wild camp at night.