You left out hundreds of lines of code that might be important.
I predict that DELAY_BFKB2 is a global variable that is not initialized as a cell.
I predict that you are trying to record intermediate results during the ode function calculation. That is seldom a good idea.
I also see from the code that you have conditional statements. Those make your calculations non-differentiable, which is a problem. The ode* routines require that the functions be twice differentiable or else the predictions are not valid.
