Indonesian PRs cannot serve in SAF?

Two Indonesian citizens who are Permanent Residents in Singapore are currently under investigation after it was discovered that they had participated in a joint military exercise earlier this month in Magelang, Central Java.
The Jakarta Post also reported that they have been “deported” to Singapore following the incident.
The discovery posed an issue as under Indonesian law, it is an offence for citizens to serve with a foreign military, at the risk of losing their citizenship.
However, Indonesian law does take into consideration Indonesians in countries that adopt mandatory national service, such as Singapore.
Under Singapore’s Enlistment Act, all male PRs are liable for National Service (NS) when they reach 16 ½ years of age, and have to register for NS. This includes those whose Singapore citizenship is a second citizenship and to male children who are granted PR status under their parents’ sponsorship.
“Going forward, Singapore will not send Indonesians to a joint exercise here. We have asked them that, and they are agreeable,” Major-General Fuad Basya, spokesperson for the Indonesian Armed Forces (TNI), told The Straits Times.
The issue, however, is not new.
In 2008, then Foreign Minister of Indonesia Hassan Wirajuda has asked Singapore to exempt Indonesian citizens who are PRs from NS, citing the same law that affects their citizenship.
In 1999, then Indonesian President B J Habibie had apparently called for the citizenship of Indonesians living in Singapore who served NS be revoked, as the country does not recognise dual citizenship.
Earlier this year, Singapore announced the formation of the SAF Volunteer Corps (SAFVC).
The SAFVC was first proposed by the Committee to Strengthen National Service (CSNS) to “enable women, first generation Permanent Residents and new citizens to contribute to national defence and strengthen support for NS (National Service).”
It is not clear if such issues with citizenship in the home countries of PRs and foreigners might affect the SAFVC.