The edge on the slot game is higher than on the dice, so the Kelly criterion allows higher bets.
The SatoshiSlot has a theoretical payout percentage of 96.5%. This however cannot be determined to the same precision as the dice, as in the slot the RTP/edge is calculated by a simulation, known as the "theoretical payout percentage" or RTP, "return to player".
The max bet on the slot game is not automated as on the dice, it has to be done manually. The slot game has many paylines, it doesn't really work well if the bet sizes on the slot game would be in increments of 14.235, 18.503, 26.322 instead of 10, 15, 25 ect.
There are similar wins with lower bets. Overall, Satoshidice paid out more than the expected value to investors since the start, meaning that the bets actually generated more to investors than the expected outcome.
If the bankroll decreases further or more investors have an opinion about it, we will lower the max bet.
Your story about Satoshi Slot has nothing to do with the story stated in your "Bet on the house" terms and conditions:
1) "You have the opportunity to be part of Satoshi Dice's bankroll" -> not one word about to be part of Satoshi Slot's bankroll
2) "Satoshi Dice keeps the maximum profit a player can make on a bet to
1.9% of the bankroll (employing the Kelly criterion)."
-> again not one word about Satoshi Slot
3) You: "The SatoshiSlot has a theoretical payout percentage of 96.5%" = 3,5% house edge
Not that it would play any role, but how much is the maximum profit a player can make on a bet on Satoshi Slot?
4) No Satoshi Slot terms and conditions and therefore no idea based on what investors would be part of Satoshi Slot's bankroll?
Please quote the relevant to be part of
Satoshi Slot's bankroll terms and conditions?
Btw, how much is the house edge for Dice?