Flight cancelled by airline, re-booked 24hrs later - compensation and expenses claim query

Franksquirrel

Thanks in advance to anyone who can help with these questions:

Very recently, several of us travelled together on the same flight from UK to Sweden for a wedding.

We all booked our flights at different times, but arranged for two of us to sit together, and for everyone else to travel on the same flights, as a group, due to disabilities and the age of some of the wedding guests (frailties & without access to phone apps and plastic for spending).

One passenger bought his own ticket and then another, for our elderly relative, who was a later addition to the wedding party. The same thing happened with another late addition to the flight, who had his flight booked for him.

For the return flights, we were all heading home on the same day, but a few took the earlier flight (those with little ones), leaving four remaining in Sweden. We were booked on the next flight out, which was cancelled by the airline, no reason given, just before we were about to check out of our hotel.

After two hours on the phone, we managed to get the four of us booked onto the same flight (leaving the next morning), as the airline had automatically booked us all on different, alternative flights. We explained that 3 of the 4 travellers had disabilities (two were older, retired relatives), and although flights were booked separately, we all needed to be on the same flight (as we were before). They messed up, booked 3 on the same, 1 on another, but we got it sorted after another 2hr call!

The airline told us they would only pay expenses for 3 of us, as we booked via the airline itself, the groom had booked the 4th passenger's flight/room through a 3rd party site.

We're home now, and started a claim for expenses: Two hotel rooms, for one night, at the same hotel we were already in (2 sharing), plus lunch, dinner, breakfast, and a cab fare (cheapest travel for disabled adults & splitting cost between us).

We uploaded receipts online and explained that 2 of us had paid for expenses for 3 of us, as 1 of the passengers is an older gentleman, without plastic and it's practically cashless where we were.
They knew all that, of course, thanks to those lengthy phone calls mentioned earlier!  We included the booking refs and names of all three passengers.

Nothing has happened (3 weeks on). We have since said we'd like to claim flight compensation too. The airline (Norwegian) has not acknowledged the request, twice sent by reply email - to the one they sent asking us to use it for any additional info.

Questions:

Can they make a fuss about 2 of us claiming for various aspects of expenses for 3?

(One paid hotel bills and breakfast costs for 3, another for taxi and other meals - on our credit cards - receipts supplied, with explanation of reason for this method of payment - age/disability)

Can one of us claim compensation for all passengers, for similar reasons as above (plus not enough hours in the day for separate chasing of these claims, on top of other life admin)?

How long is too long, for an airline to settle these claims? Credit card interest on these bills will become an issue soon! (Weddings are expensive enough, with extra costs accrued through no fault of our own)

Sorry for lengthy post......Any help greatly appreciated!