Hi, and welcome!
Thanks for the reproducible example, called a reprex. Always helpful.
best_migramod
calls fit_migramod
; after you initially capture x \& y with
x <- dataIn[, 1]
y <- dataIn[, 2]
the call to fit_migramod
is
valSim <- fit_migramod(dataIn, parameters_0 = param_0, model.rc = model.rc)$values
which hasn't been modified as it was earlier.