How well this works depends, generally, on how you set it up.
SCORM requires communication with an API on the LMS side, and generally uses Javascript to communicate between the lesson and the LMS API.
Javascript, however, has security measures to prevent 'cross-site scripting'.
So if your lesson is served from one URL and your LMS is on another URL, SCORM communication between the two can be...difficult to impossible. Per spec, the LMS should launch the lesson...the lesson doesn't HAVE to reside within the LMS, but if it does not, JS limitations restrict functionality.
SO when you you say, "store all course files on our internal servers and then 'point to' the course files using the LMS on our vendor's servers" - how exactly are you doing that?
Your Vendor replying, "Captivate course is not consistent with its remote SCORM or AICC delivery methods" seems odd. AICC does indeed allow for remote-content (I've little experience with AICC so can't detail that, nor how Captivate's AICC methods work)...but SCORM does not. There is no official 'remote SCORM delivery method' to be consistent with...that I'm aware of.
The new TinCAN specification WILL allow such communication, but it's not a minor tweak and will need to be supported by not only Captivate (it is not yet) but the LMS as well.
Now, it is possible to integrate lessons into an LMS that pull their content from external servers, you just have to be aware of the JS limitations...and it may indeed be difficult or impossible to do with Captivate... How are you trying to do it?
