All growth factors have very specific effects, so you cannot really substitute one for another.
And a study found HGH provided no major benefit for ME/CFS patients.
Though there was once a patient on this forum who was diagnosed with ME/CFS for 10 years, but it turned out she had HGH deficiency, and all her symptoms rapidly disappeared once given HGH injections.
However, apart from that, I don't think HGH will be of any great help for ME/CFS. I tried a few short courses of HGH 1 IU daily injections a few years back, and it did not help me.
@Hip do you remember the members name that took the HGH?