The "turned wood" style of the knob on the brown piece is strange and looks kind out of place in an otherwise modern style. A similar style can be seen on a blue tazza ref RSW52 on page 22 of the King's Lynn 2004 exhibition catalogue.That piece has a central bauble.
The bauble (knop) that you mention from the stemmed fruit bowl is hollow. The finials on both Terry's pieces seem to be solid and to my mind are too 'mean' (or small scale) to be by RSW. With the other contrary features (wrong colour/ lids/ solid stem) it suggests that perhaps the intial thought about RSW might be wrong.
Currently there is no one book on the subject of Wuidart, Leamington, Kings Lynn, Wedgwood, RSW. Oh, by the way two "N's", two "T's" and two "L's" in Ronald Stennett-Willson. I had to be told, so I thought I'd flag that one up.
The exhibition catalogue " Ronald Stennett-Willson, Glass Design 1954 - 1980" is the only publication that gives a representative history with photos. There is information in Sally Tobin's book "Wedgwood Glass" Tobin, 2001, in Ronald Stennett-Willson's "Modern Glass", Studio Vista, London 1975 and in "20th Century Factory Glass", Lesley Jackson, Mitchell Beazley, London 2000.
Nigel