perfectly fine. i mean, its transparent, so, not really a hiding place, but if the snake desnt mind because it feels secure in the enclosure anyway, then thats not an issue.

about bacterial growth: the moss is actually wet. you make it wet before you put it in. so the humidity in the air is completely meaningless for the bacteria in the moss. the reasoning doesnt really make sense, it would be like saying that inside a pond, its more humid when its raining and less humid on a dry day. the fish would disagree until the pond actually dries out.

so, how many holes you put in only affects how fast the hide dries out and how humid the air inside will be.