Reverse Swap: chosen claim tx feerate not applied correctly when paying to P2TR

[ok300]

The customer reported this claim tx: https://mempool.space/tx/3afcf2196c238021b99f77efdae078e42ab581ca279076601898ded5b38e3305

where the chosen claim feerate was 4 sat/vB:

    "onchain_amount_sat": 183058,
    "sat_per_vbyte": 4,
    "receive_amount_sat": null,
    "cache": {
      "status": "CompletedSeen",
      "lockup_txid": "1714461275fae9db53f47e597611c14d410fb62b7fe3a656730790d5bae45648",
      "claim_txid": "3afcf2196c238021b99f77efdae078e42ab581ca279076601898ded5b38e3305"
    }

However the actual feerate used was 3.09 sat/vB.