You've only taken pictures from the inside.
Was your intention to build up inside the glass blocks or were you thinking of removing the blocks completely?
It's not a problem to build regardless of which option you choose, but removing the blocks means you'll have to plaster on the outside, right?
That means more work + it may not look as nice against an already plastered plinth.
I would have made it easy for myself; masked the glass blocks and applied a silicone joint to the seams, both inside and outside, to make it tight.
When you smooth the joint, use plenty of soapy water.
Glass blocks have the advantage of letting in light (at least more than a built wall

) and like bricks, the material doesn't rot....
By the way... are you sure the moisture is coming in right at the glass blocks? You should perhaps consider why water is coming in on a wall surface. How does drainage and runoff from the house wall look?