Assuming the wording is the same as my contract, they don't offer a credit, they guarantee to repair or replace if the production is not met.
Post #78 in my thread. Tesla has come out once so far on a production flag (at their initiative, I never called them, just got a text out of the blue that I had a service appointment, post #95) and replaced 2 of the 5 RSDs, though I haven't seen any change in production since they did that, so I suspect they'll be calling again.
So are they offering financing for the Solar Roof now? They had called me a while back asking if they could show a financial institution my roof as they were making the pitch for financing support, I told them I was fine with it and never heard anything more.