With just a limiter at the end of a mix, I would patch the MIX OUT of the last Bus Depot to the Limiter. Then take two outputs each from both the left and right outputs of the limiter. Send one pair to your card and another pair to something like an analyzer. That’s one I would do.
You can also use another Bus Depot. It works well to have your pre mastering mix to the first Bus Depot, then any mastering effects (EQ, compressor, limiter, etc.) chained before aux inputs to the final Bus Depot. They are lightweight modules. For example, use multiple Bus Depots to create mix groups. Use an extra Bus Depot to check the output of a limiter. To be clear, a master mix effect does need to happen after a Bus Depot combines all the buses.
Thanks for trying them out!
p.s. And one final option, but not for a limiter, with some effects you can apply them to the polyphonic bus cable before a Bus Depot (but that depends on the type of effect, and depends on if the effect supports polyphonic cables).