The US dollar volume is already shown on exchanges that are trading USDT as it is traded directly into the US Dollar (USDT / USD). I'm referring to exchanges like Bittrex and Kraken.
What I think you're asking about then is a pair like BTC / USDT where there are no ties to the US Dollar at all and you want to somehow verify what is the tether traded really worth. In short, no this indicator can't do that kind of comparison; however, it may be a question worth answering.
We can do this a couple different ways. The first, and by far the easiest, is to believe that for every Tether there is a US Dollar and therefore the volume is in fact real. Or we can ask a question like "if I had to convert the Tethers to US Dollars on a different exchange before purchasing this Bitcoin, how many US Dollars would this transaction be worth"
Lets look at an exchange like Binance with the pair BTC / USDT. The volume is listed by coins traded (Bitcoin) from the exchange. If you bring up this indicator, then it will display the volume of Tethers that were paid for those transactions. You would then have to compare this figure with the price of Tether on an exchange like Kraken.
Something like realUSDVolume = tetherVolume * tetherPrice.
Keep in mind the limitations of something like this as price may be different on exchanges, the actual liquidity of the order book may be too thin to sustain current price, and of course that Tether may in fact be backed one to one with US Dollar.
I hope this helps, good luck!