if Luxor stopover is a problem

I'd take evening flight to Aswan right after arriving from Amman. Leave you Mena house staying for later until after cruising and arriving Cairo from Luxor, and you can choose to stay in Mena for as long as you want before flying out of Cairo. As for airfare, I booked the only available bogus business class fare. 
For Nile cruise tickets, what I heard is that you can't get confirmation until about 3-5 days prior to cruise date, regardless if it's Misr or viator, they kind of try to consolidate people all together to cut cost, which I understand. 
I don't have luggage issue since I'll take them with us to ABS, and I don't know if the free shuttle bus will still be running in the afternoon when we arrive, we'll take taxi to hotel anyway.

As for your friend, I don't know the details, but I would get myself home first, let airline deal with my luggage delays, because coming home is different from going away for wedding. 
 

Btw,I checked with st Regis Cairo, they would give breakfast for 2 to Plat members as welcome gift.