Exploring a trust-minimized KRC-20 to KCC-20 bridge on Kaspa without relying on a relayer

As far as I understand, the state of the indexer can not be reached from within Kaspa. The indexer simply tracks revealed txs scripts (and not their payload field, note that KRC20 protocol was created before the introduction of transaction payloads in the Crescendo upgrade.

What is “RTD Rollup”?