I'm pretty confident that JBL never made a 4" aluminum domed diaphragm ( yes the titanium variety came in 8 ohms and has a low dcr of about 4-5 ohms > and will have a green dot of nail polish on the diaphragms positive connector ) .
All bona-fide JBL 2441's are labeled 16 ohm.
JBL's ( labeled 16 ohm ) large diaphragm drivers typically have a DCR that measures around 8-9 ohms ( IME ) and will have a red dot of nail polish on the frams positive connector.
Your diaphragm that measures 14.7 is either a cooked JBL diaphragm or it's an aftermarket.
In all my years at this forum no-one has ever provided any proof that buying a Chinese after-market diaphragm was a smart move ( JBL or Radian are the only 2 choices I would recommend) .