It's not provably fair. To make it provably fair you need to show information which will allow players to know that the result of the draw can not be influenced by you before they make a deposit.
A possible implementation is the hash of the random seed (possibly add some salt). You will make people even more happy if you use the incoming transaction id as the client seed in addition.
The only way to do what you ask would be to show the cards before hand more or less.
Even if I hash the random seed with/without salt I would still just be displaying that to user after the fact. Using the trans ID as the seed might work would need to research a little see exactly where these comes from IE there is no pattern there or the system would basically be exploitable.
Random is what random is No good way to be random and at same time not have some part hidden. Else it would be predictable and thus not random anymore.
Just looked into it and the TX Id is a hash of the TX which in theory could be built in memory and figured before hand thus basically knowing your outcome before it happens so yeah not doing that.