I'm confused, what does SIP have to do with this? I use lpadmin to create printers and just point to wherever the printer drivers were installed by the vendor package.

I was under the impression that this area where the printer drivers ate installed is protected. If not then im confused as to why im getting an incompatibility issue with the lpadmin script.

Heres the script that is causing sips issues

lpadmin -p Printmono -v SMB://student-print.lboro.ac.uk/student-mono -P /Library/Printers/PPDs/Contents/Resources/RICOH imagio MP C5000.gz -E -o auth-info-required=negotiate -o printer-is-shared=false -o printer-error-policy=retry-current-job -o OptionTray=2Cassette -o ColorModel=Gray

Have you tried disabling SIP to confirm it is actually the issue?
I have been adding printers using scripts since SIP was added and have not had any issues.

Yes, ive disabled sip and the script runs fine.

Im begining to think that its not the script but the actual composer package.

Where does Composer fit in? My printer deployments consist of a vendor pkg (which I install like any other pkg) and a script that adds the printer with lpadmin. Are you repackaging everything into one pkg?

Yes im packaging the drivers in composer and use the script as a post installer.

In most cases, @Jivebunny there is no need to repackage printer drivers. You simply upload the vendor provided installer .pkg file and install it. You can use the Files and Processes payload to run the lpadmin command. We use Ricoh and Konica Minolta copiers and I've not had to repackage installer .pkgs from either manufacturer.

If you're going to use Composer, you've probably just got to make sure that your .pkg is signed. This is supported by Composer. Just check Composer's Preferences. You will need an Apple Developer Account. That said, I agree with @mpermann you generally should not need to repackage everything. You only really need to get print drivers to users computers (manufacture .pkg should work just fine) and then use an lpadmin command (or larger script) to install your print queues.