LMS Information Request

I am gathering information for recommendations regarding a customer facing LMS. Specific requirements include:
-SCORM 1.2 and 2004 4th Edition at a minimum
-Ability to handle 20,000+ customers/ users
-An "empty player" type of functionality (allow SCORM package to play in separate window within the LMS environment)
-Virtual training capability
-Works across all web browsers and platforms (both PC/ Laptop and Mobile)

-Also looking for any information/experience you may have with xAPI / Tincan as alternative to the earlier versions of SCORM

Please let me know what recommendations you may have (may reach out to me directly if need be at Joshua.mcfarlin@I-CAR.com)
Thank you