How to make texture streaming system use render target's camera as viewinfo?

I’m using multiple SceneCaptureComponent2D to render various render targets for my characters. Then I put those render targets in a UI canvas, but I noticed that the character textures in the RTs were very blurry (low-res mips). I tried to do r.Streaming.Boost 100, which makes all the textures sharp (high res mips)。

I think the problem is that the streaming system only uses my main camera for mip calculation. Suppose my camera for UI rendering is far from those characters. In that case, it will think I’m rendering them far away (even if the ScenecaptuerComponent is close), so a low-res map will be loaded (if high-res maps are not already loaded).

How can I make it load the high-resolution mips for characters in RTs? (with streaming on, should not affect other scenes)

and texture streaming will keep high res mip if the budget allows, even if I’m far away?