I have a number of gecko species that eat the fruit nectar and live insects. Some of them eat both and some prefer one over the other. There are brands of fruit nectar in the US (Repashy and Pangea) that have bugs in them. If you can get that, you could see if they'll eat it.
I checked the ingredients on the internet, and it does list "insect meal" so I guess it does have insects in it. It's probably worth offering small crickets periodically because they may change their mind about eating them.