Congrats on unlocked blue star 
The minimum bonus for hitting plat1 is $200 but the extra $170 is probably for losses during gold to plat.  The special platinum 3 is more lucrative due to the perm reloads and VIP host. A few weeks ago, VIP host was for plat 2 too but they changed it to plat3 and in few months probably an extra million should be wagered for plat 4 in order to get a host and reloads.