Need to make a bi-ped to quadriped humanoid character rig for a game

[Cieroceramics]

I am in a bit of a pickle here and I kind of need to save this rig I have made into a real big mess.
the character is a biped demon like creature witch a stretchy tongue.the character model is based on humanoid model but is meant to shift into quadruped.
I want to explain my process of how I made it, and if there is any heroout there who is willing to check my practices then I am fully willing to listen.
My first mistake was targeting it to Human IK, which did not know that character was quadruped, and other characters needed mocap targeting, but the animator completely rejected it.

I created the new rig in 3 days using one skeleton because I thought that was how it had to be for games. I know now its not true but it might be too late to go back and change the setup,
despite already causing issues
the characters arms, legs and spine have IK/FK switches that change which curves constrain the joints.
the hand has 2 IK modes.
normal hand, and reverse foot hand for quadruped mode.
again all constraints are set driven to the IK mode as well.
IK mode for hands is a ENUM switch because I don’t know how to do a ternary set driven keys.
the hand CTRL is orient constrained to the wrist in YZ and forearm in X.
I thought this was the way to go but it breaks. both in hand and foot mode. my feet are pretty solid and they use reverse foot so I’m pretty confident with the setup.
I also don’t have any controls for the normal hand IK fingers because I don’t know what the animator wants. (they keep spitting back the rigs with weird breaks)
also somewhere down the line the entire bone structure shifted from the original pose, which terrifies me for if I have to go back and reskin the model. (which took also a really long time I probably cannot spend again) and re drive the orient constrain weights to the proper control curves(again, wayyyy to much time)
arms and legs (in IK mode only) have stretch(using translateX), head and spine has squash and stretch(using scaleX).
scaleX squash and stretch effects every child bone in the game engines hierarchy.

at this point in my post you all might be wondering how in the hell this guy got a job as a rigger?
I know some of my standards are a little rusty, but I am really hoping to nail this. and deadlines are like. soooo passed,.
I am desperate for anyone who could give a helping hand or make any comments as to how I have structured this thing. or even comments as to how I should have done it from the beginning.
going back and restructuring at this point is not really going to fly with the director because he needs animations yesterday.
really hoping I don’t blow my dream opportunity here.
is it possible to save this thing ? or my contract?
edit: I also left out one of the tongue influences by accident, so reskinning at this point seems almost inevitable.

[Technically_Artistic]

On the wrist, I assume you have the hand joint a child of the wrist. Don’t do that for the reason you are running into. Have the wrist and hand both a child of the forearm and then just have the rotate X of the hand drive the wrist.

What’s going on with the rig breaking? Are you hiding/locking visibility on all the parts you don’t want the animators to touch?

On re-skinning, can you not save a duplicate, move the two skeletons to overlap and copy skin weights over? I do that all the time to transfer weights. Reference in a backed up scene with good weights to put on the new mesh. Sorts by name, one to one, and then closest joint I think in the options.

You might want to toss it up on dropbox or a google drive or something for people to look at if that doesn’t break an NDA. I don’t hear anything super out of line there, but maybe there’s things I’d see in the scene that I might consider issues that you don’t?

I typically build my rigs so that controls are separate from joints, IK, clusters or anything else driving the rig, so I have a hierarchy that is just controls and group nodes for the animators, so that when the show/hide stuff they can’t turn on any of the rig and/or accidently select parts like joints or IK. So if you didn’t do that, and animators are grabbing rig parts and keying them or accidently moving them without realizing, that has definitely broken some rigs I’ve seen before.

I would also make sure you don’t have any dependency loops going on in your rig. Like when you move a control or something a yellow warning doesn’t come up in the script editor about a cycle dependency or something.