The casino made what I assume is a promise to op that if he could own up and agree on cheating or trying to cheat the casino by operating two accounts, and also writing an apology note on a public forum like this one, that they will allow him withdraw his initial deposit and maybe winnings from slot games.
I guess in that case the casino should at least allow OP to withdraw his/her initial deposit if not the winnings. OP has broken the terms of the casinos and it will be good fate of the casino to allow withdrawal of the initial deposit. I believe most people on this forum who might operate multiple accounts on online casinos should better read the terms and conditions first and avoid creating multiple accounts.
Well, I completely agree with you as regards to the casino allowing op to withdraw his initial deposit, since as it is, he has fulfilled all the supposed request of the casino.
But on the other hand and in my personal opinion now, casinos hardly forgive, specially when a gambler outrightly broke their terms of service and its visibly agreed to by everyone one.
So in this case, I am assuming that the casino may want to still hold the funds for some time to further teach op a lesson, but all the same, I have not read from op recently to know what exactly is the current situation of this case, maybe the casino have allowed him to withdraw his funds and he is yet to update the thread.