I disagree.
I mean I bet this game has millions of lines of code, but I bet they didn't make it hard coded everywhere or really hard to modify (that'd be bad programming practice and I highly doubt this game has those).
Like there's a range function which is probably just a random number.
C++ it's:
// Normal KF, Random value between 300 and 310.
LightRNGValue = rand() % 11 + 300;
Just change that to LightRNGValue =310 if you want guaranteed. Just like challenge mode gives. Or up the range so it only gives 305-310 instead of 300-310.
A 2nd semester programming student can make these changes so that part takes 0 work.
To use their tools and make a production ready patch however, seems to take the longest time.
I don't know anything about software development so can't comment on that aspect lol