Not sure what your point is. Sure, the 3-letter agencies have an investment arm, but the capital used for those investments is a tiny fraction of their operating budget. And that capital still comes from Congress' appropriations.
The parent previously offered that three letter agencies would require an investment arm to sustain themselves. In that context, I offered that they had one. I can't claim any knowledge about the profitability of that group or what portion of funding is provided by that group which is relevant and you have added perspective on. I have personally experienced InQTel as an alternative funding mechanism which argues against it being a serious funding source.