Not sure if IPC or UPC, but....
2018 UPC
1014.3.4 Location. Each grease interceptor shall be so installed and connected that it shall be easily accessible for inspection, cleaning, and removal of the intercepted grease. A gravity grease interceptor that complies with IAPMO Z1001 shall not be installed in a building where food is handled. Location of the grease interceptor shall meet the approval of the Authority Having Jurisdiction.
1014.3.4.1 Interceptors. Interceptors shall be placed as close as practical to the fixtures they serve.
The final sentence of 1014.3.4 and then 1014.3.4.1 may loosely give the AHJ opportunity to say that discharge must be gravity fed to the grease intercept. IMHO, this would be justifiable, as the grease laden waste may interfere with the pump serving the force sewer line.
However, it would presumably be more of a maintenance issue. The grease will build up in the force sewer line and in the pump tank/reservoir, which could present issues with pump longevity and serviceability. But again, that is a building owner maintenance issue.
The reason that I point to this building a maintenance issue is because the intent of the code requirements for a grease intercept is to protect the public sewer line. Therefore, the intent is only that a grease intercept be provided before connection to the public sewer main. For this reason, I would most likely not prohibit/reject the proposed configuration, but would not be in support of it either.