Sticky Gaps in Diamond Painting

Hi,
our family has already done quite a few diamond painting projects.
In some of them, there are sticky spaces where no diamonds end up—like on the snowflake keychains, for example.
Of course, the adhesive is pretty strong, which is actually a good thing since the diamonds are supposed to stay in place, but unfortunately, dust and dirt from my purse also stick to it really well 😅
Has anyone ever tried using puzzle glue on these? Does that get rid of the stickiness? Will the diamonds still sparkle?

Hi, all I know is that the rhinestones still sparkle beautifully when you apply puzzle glue. But there is also special diamond glue.

Best regards 
Sigrid