Homosexuality is grounds for a legitimate claim for refugee status in Australia where you may be persecuted in your country
This UN report explains that where a person fears persecution because they are homosexual, that persecution (membership of a particular social group) may form the basis of a legitimate claim for refugee status which signatories to the UN Convention will be obliged to recognise.
In that case non-refoulement principles would apply and we could not send a person who successfully made such a claim to a country where they would be further persecuted, as would happen in PNG with 11 years gaol.
Here's the case most often cited in Australia where the Administrative Appeals Tribunal heard the application of a man who said he was gay and found that we owed him protection from authorities in Lebanon.
Download Homosexuality persecution grounds for asylum (Australian application)
Here is the law in PNG regarding homosexuality
Stand by for a sudden mass conversion.