I think the reason it was one of the exhibits handed back (as well as the ownership problem), was the age of the sign. It had featured on the museums old website until this year, but was not in a very prominent position in the display areas.
I think the medals are another matter, he earned them through courage and self sacrifice, a little different to having something handed over for free when you happen to be setting up a museum.
Tangmere runs with total volunteer staff, many of whom are now well over 70. This has not prevented its continued growth, despite ever increasing government bumph being thrown at it every year. I have made small contributions over the past 2 years, but for some of these (some ex WW2 veterans) this is a focal point of life. To see exhibits sold this way is heartbreaking for them.