The odds work on averages. The $5M prize should only come out every 126,667 rolls (3,800,000 odds / 30 tickets to a roll). The fact that two came out this quickly likely means that there could be a real drought in top prizes for a while or at some point down the road.
The same thing happened in the $10M Misfortune game. The first $10M prize hit relatively early in the game cycle (somewhere in the low 100k range) when the overall odds are closer to 1 every 202,500 rolls (8,100,000 odds / 40 tickets to a roll). We are in the mid-300k roll range here in Jax and there has not been another top prize hit yet. And it could be a while longer. From what I have seen on the frequency of top prizes hits, there is variance with some being hit closer together and some being hit further apart. But the average eventually stays the same. Otherwise at this rate, the last 4 top $5M prizes will be claimed before the game is half way through the distribution cycle which is not likely to happen.