Flying 4/12 LAS-DFW (AA J)-LHR (AA F); 4/22 CDG-LHR-LAS (BA J A380) - LAS (AA J)

1) I have both tickets on one PNR but we're not going to the airport together. I just plain forget, will I be able to check us both in on my phone and then forward one of the boarding passes to her?
2) The OTW flight leaves at 11PM, and we'll have FFD in DFW. Will they let us move around the meal service time-wise?
3) The CDG-LHR flight will be European "business" - front of the plane, regular economy seats, middle seat blocked off, right?
4) What lounge(s) would we have access to in LHR during the connection from CDG? We have about 3 hours.
5) What will the food be like in BA business class? Is there any pre-ordering? We have our seats selected, 53J/K
6) Are there any neat amenities on the A380 upper deck available to J pax?