That headers looks pretty reasonable to me. I don't see anything misleading or ambiguous about it. Whenever I am heavily modifying some licensed code, I always make sure to include a similar header.

    > I'm going to ahead and say there are copyright law nightmares, right here.

    // SPDX-License-Identifier: ISC
    /*
     * Copyright (c) 2010 Broadcom Corporation
     */

It adds a contributor.

To add a contributor, you need "significant" _human_ input. The output of models has so far not been deemed copyrightable.

As it acknowledges the original source, it needs to show the human effort that allows it to be bound to the new contributors.