mathematical optimization – How to minimize a problem with differential equations in it?

My problem is to minimize a target function with differential equations in it.
The target function is $$min mathrm{J}left( p right) =sum_{i=1}^5{|x_ileft( p right) -y_i|},,$$
where $x_i(p)$ are differential equations like this:

stateFunctionV(v1_, v2_, v3_, v4_, v5_, v6_, v7_, v8_) := {
(Mu) = (67/100)*(x2(t)/(x2(t) + 28/100))*(1 - x3(t)/940)*(1 - x4(t)/1050)^3*(1 - x5(t)/361);
x1'(t) == (Mu)*x1(t),
x2'(t) == -(v1 + (Mu)/v5)* x1(t),
x3'(t) == (v2 + (Mu)*v6)*x1(t),
x4'(t) == (v3 + (Mu)*v7)* x1(t),
x5'(t) == (v4 + (Mu)*v8)* x1(t),
x1(0) == 0.2025, x2(0) == 441.337, x3(0) == 0, x4(0) == 0, 
x5(0) == 0}

and $y_i$ is the experiment data.

The code:

PIP1(value_) := {
Sum(Sum(Abs(
NDSolveValue({
(Mu) = (67/100)*(x2(t)/(x2(t) + 28/100))*(1 - x3(t)/940)*(1 - x4(t)/1050)^3*(1 - x5(t)/361);
x1'(t) == (Mu)*x1(t),
x2'(t) == -(value((1)) + (Mu)/value((5)))* x1(t),
x3'(t) == (value((2)) + (Mu)*value((6)))*x1(t),
x4'(t) == (value((3)) + (Mu)*value((7)))* x1(t),
x5'(t) == (value((4)) + (Mu)*value((8)))* x1(t),
x1(0) == 0.2025, x2(0) == 441.337, x3(0) == 0, x4(0) == 0, 
x5(0) == 0}, {x1, x2, x3, x4, x5}, {t, 0, 6.5})((i))
(data2((i, j, 1))) - data2((i, j, 2))
), {j, 1, 7}), {i, 1, 5})}
NMinimize(PIP1({v1, v2, v3, v4, v5, v6, v7, v8}), {v1, v2, v3, v4, v5, v6, v7, v8})

doesn’t work. I also tried to take the differential functions out as a new function and it also failed.

So I wonder if there’s a way to minimize this problem with NMinimize or not? I would be grateful for your advice on how to couple NMinimize and NDSolveValue.

The experiment data are below:

data2 = {{{0, 0.2025}, {2, 0.76}, {3, 1.28}, {4, 2.2}, {5, 2.75}, {6, 
     2.95}, {6.5, 3.055}}, {{0, 441.337}, {2, 400.435}, {3, 
     300.326}, {4, 219.348}, {5, 120.109}, {6, 50}, {6.5, 25}}, {{0, 
     0}, {2, 42.2895}, {3, 78.6579}, {4, 117.026}, {5, 152.158}, {6, 
     229.553}, {6.5, 224.1205}}, {{0, 0}, {2, 1.66667}, {3, 
     13.55}, {4, 16.6667}, {5, 22.7333}, {6, 34.4333}, {6.5, 
     71.2333}}, {{0, 0}, {2, 6.73913}, {3, 7.86957}, {4, 9.3913}, {5, 
     8.34783}, {6, 10.9565}, {6.5, 11.8261}}};