Rubuta ci gaba ga wannan sakin layi - Japan ta mika wuya a hukumance
a ranar 15 ga Agusta 1945, kuma Indonesia ta ayyana 'yancin kai kwana biyu bayan haka. A safiyar ranar 23 ga Agusta, 1945, Adnan Kapau Gani ya gudanar da wani taro don tattauna gwamnatin bayan samun 'yancin kai na Kudancin Sumatra. Mohamad Isa, wanda ya halarci taron, ya rike mukamin shugaban harkokin mai da hakar ma'adinai a Kudancin Sumatra. A matsayinsa na shugaban harkokin mai da hakar ma'adinai, an nada Mohamad Isa a matsayin Shugaba na PERMIRI ("Perusahaan Minyak Republik Indonesia", Kamfanin Man Fetur na Jamhuriyar Indonesia). PERMIRI ita ce kamfanin mai na farko a Indonesia wanda Indonesians ke gudanarwa. PERMIRI ne Adnan Kapau Gani ya kafa kuma ya sarrafa ragowar matatun mai a Kudancin Sumatra, wanda NIAM ("Nederlansch Indie Aardolie Maatschappij") da BPM ("Bataafsche Petroleum Maatschappij") suka mallaka a baya, dukkansu kamfanonin mai ne na zamanin Dutch East Indies. Babban aikin Mohamad Isa a matsayin Shugaba shi ne gyara matatun mai a Plaju (wanda BPM ta mallaka a baya) da kuma Gerong River (wanda NIAM ta mallaka a baya). Dukkanin matatun biyu sun sha wahala sosai saboda kamfen din bam din da Allies suka gudanar a shekarar 1944.