He asks: “I’ve also requested in LHPs that she communicate with my friend in dreams, to help ease his burden, but so far he hasn’t had any. Why is that?”

There have been dreams, but simply dreams not recalled consciously. The greatest benefit is to the deep subconscious which is beyond conscious awareness to begin with. So, it is only those things shared in the dream state that are overheard and seen at times, by the upper subconscious, and then witnessed and retained in memory through a lucky juxtaposition in being awakened while a dream is underway, that they will be recalled and appreciated consciously. So your desire for this to be a source of assistance and reassurance is being enacted within the most important part of the mind, at least.