Maybe he is still playing in some international leagues, and he is also old now with the age of 35 years old. The Gilas were the better team with him, but not only because of him, it's because they have a good coach who knows how to use the players.
I've looked at his official Twitter account and the last tweet that he made was on September 2019 and that's already 3 years since he's with the team. Time really flies so quick.
His last season is 2016–17 with Xinjiang, I think it's a team in China, that's according here. https://en.wikipedia.org/wiki/Andray_Blatche
Well, I guess he is now resting, or probably have retired in basketball already, but if Gilas will look for a big man, it should be a young one that can still play heavy minutes and will be a huge help to the team.
In terms of hiring new Naturalized player, Brownlee is the one that being push to get that position, though unlike Blanche who really have the height and the impact inside and outside but chemistry wise he might bring good lifting help to work side by side with Clarkson, we do have Fajardo, Kai and Aguilar who can run with these two offensive attackers to support the rim and bring offensive rebounds.
Though it might need more time to create a system letting everyone to jive with each other's game, but talent wise if coach will take time to really focus with the nationals we can reestablished the name that we already created as Asia's one of the top basketball athlete.