Hi @R.E.M Welcome to MadeForTrade community
All details about Dhan’s Risk Management Policy are available here, including that of Commodities - Risk Management Policy | Dhan
Margin requirements as now are specified by exchanges, they are standard and brokers have little control over them.
You can also go through this post, about Commodity Trading experience on Dhan Commodity Trading Experience on Dhan - Simple, Smooth, & Seamless!