Blue could have a point here, I do that if you contact halve dead support, besides not been helped, you will find out that they keep track of the gems purchased but have no clue of the free gems that you have. This is the only game that does that. Clash of clans keeps track of both. I've checked that out with both games. The gem roll manipulation could be a good theory, I will need to find another cc player to test that out but so far finding another player has been pretty hard
I just rolled another 900 gems, all blue. That means I've rolled 92,100 gems straight and have only gotten blue heroes/blue slimes from them.
I'm also on day 169 of blue hero/blue slime from the daily free roll.