Just made a simple test to se the differences in the bitcoin2john outputs. Below are 3 hashes:
test: new wallet with password
12aVP18cd5XsbcGQy8u6eywQ6UuA6Q319stest2: the same wallet but with password
1test3: the same wallet back with the password
12aVP18cd5XsbcGQy8u6eywQ6UuA6Q319sResults:
C:\Users\mrc\Desktop\test wallet>python bitcoin2john_r.py test.dat
$bitcoin$96$
a1e8d2b8ee3e95495e2e860a28c1ba0b78a0ff9bc9be43730d246b0b23fe18ec43d24fc9ba55441 cdb60c04a1120e738$16$
a782de2216ac5636$277777$96$
775421c1db2bc628932d3c480ce3f5b669359c5a73dac7726d59e2ba7154d48fe7ff468dc14c16c 5d2acef18bc4dda93$66$03ffee576a1930d9891832fd90b98c510537cb09e5e934d33b8ec75cf883a43778C:\Users\mrc\Desktop\test wallet>python bitcoin2john_r.py test2.dat
$bitcoin$96$
f001c37f1ff094dfcb05092a9047d6332a88333b636d6ff13cc71c38d39e737eab565ca9a09f12e b8e823a3213ff1920$16$
a782de2216ac5636$281999$96$
775421c1db2bc628932d3c480ce3f5b669359c5a73dac7726d59e2ba7154d48fe7ff468dc14c16c 5d2acef18bc4dda93$66$03ffee576a1930d9891832fd90b98c510537cb09e5e934d33b8ec75cf883a43778C:\Users\mrc\Desktop\test wallet>python bitcoin2john_r.py test3.dat
$bitcoin$96$
b016c42c35bbd3924a2b2aa1f5a99b0cd434ce7f805fe7d670ab98ce262d9b38045500ba9934f24 f1b01257b923de915$16$
a782de2216ac5636$277823$96$
775421c1db2bc628932d3c480ce3f5b669359c5a73dac7726d59e2ba7154d48fe7ff468dc14c16c 5d2acef18bc4dda93$66$03ffee576a1930d9891832fd90b98c510537cb09e5e934d33b8ec75cf883a43778The first and last test have the same password and the same PUBkey and wallet version, any thoughts

Yes, the wallets that have the same iteration are simply the same wallet hex edited over and over again with what ever public view key they desire on the same wallet they have made. Not changed in bitcoin core to give new string like you have done above.