I have not heard back from my last query.
Whether castration will help will depend upon what is found to be the problem. If there is a problem within the testicles, themselves, then castration may be helpful in easing the pain. Castration is usually considered to be a last option for most problems after other treatment have failed, but it may help ease pain.
Castration is not as likely to help improve arousal, at least not by itself. Certainly, if the pain is preventing arousal, removing the source of the pain may help. But the testicles are also the source of testosterone, and low levels of testosterone also lead to problem with erectile dysfunction. Therefore, there would also typically need to be testosterone replacement.
However, there is also the possibility that the underlying problem is actually involving the epididymis, which lies on top of the testicles, collecting sperm from the testicles that then travel up a tube towards the prostate and urethra. If this is the problem, then castration will likely not be helpful for relief of pain or improvement in arousal.
If you have any further questions, please let me know.