I am not familiar with this Gyaritus. I have only 2 Gyaritus species from Borneo (3 specimens total)
I sent you some photos of types on a flash drive, which included at least 4 or 5 Gyaritus from Borneo. None of those type photos match this species very well. I'm still missing a couple of type photos of Bornean Gyaritus which are in Bruxelles and Stockholm.
There is also a good chance this species is undescribed. Breuning's paper from 1979 on Gyaritini is not going to help, as his descriptions are very short and shallow.