This could be an very interesting scenario. OTL, when the Portuguese left East Timor in 1975, the leftist FRETILIN came to power. No matter how small East Timor is, This spooked the hell out of Indonesia, whose under Suharto, already became a rabid anti-communist. So Indonesia invaded East Timor (under the blessing of US and Australia, of course

).
If Indonesia went fullcommunism and FRETILIN still came to power in East Timor, ironically we could see an East Timor fully supported by Jakarta. Although if the US actually deploy troops there, they could prop-up anti-communist faction (could be the UDT, which ironically IOTL many of its leaders supported Indonesian annexation of East Timor ) as the legitimate government there once the Portuguese left......which could give us an even more interesting probability, that is, Indonesian support of FRETILIN against US and Australian backed government.