Revisited this and after updating Vagrant happy to concur no issues in creating "Sailfish_OS-patched-for-f5321-3.1.0.11-f5321-0.2.1.17" on Mac
(although, despite having flashed 3 SXC's at least 10 times total, im still not too clear on who picks up the changes to droid-compat-f5321, and where, when i run the patcher in vagrant)