It's pretty important to maintain the ability to swallow (or we 'forget' how to do it), so it's really good that he will be seeing a speech pathologist -- It takes a lot of time to adjust to our new boundaries, and suffering from that goldurned radiation is not a picnic -- I certainly wouldn't want to go through that again!

The PEG is really not much of a problem once one gets used to it (except cleaning up the 'food' spills.

Your job is to give him a lot of moral support and human contact, and see that he can get enough rest when he needs it -- It's an unseen enemy that he is fighting right now, so expect that he may occasionally let some of that wrongly spill over on you.

Keep coming back here and asking questions; pretty soon you will be answering the questions of others.