Best wedge anchors according to redditors

The stand is tripodal so you simply need something that can withstand the weight at those three points.

wickedpissa mentioned bedrisers which is the right idea - support the stand at it's three points with minimal equipment - but could be a little low on substantiality (not a word but best describes what I mean).
Because the stand will be much bulkier than, say, a bed riser, it will be prone to knocking the riser over. Something with more mass such as concrete block would not be prone to such a problem and would give you about 6 inches of rise.

Your next issue to overcome is that the rising of the stand will place the center of mass at a greater height than what the stand is designed for. When too high, the stand is liable to fall over. This can be resolved by either A) attaching to the wall (as seen in many tall pieces of furniture) or B) attaching the stand to the risers.

What I would do is take three concrete blocks from your local block and brick supplier and cover them in carpet (for aesthetics). Next, just plop the stand on top. Then use concrete or drywall anchors to bolt a wire to your wall. Then attach that wire to a point near the top of your stand to keep it from tipping.

This is the ceramic blanket I purchased a few of. It doesn't mention naked flame though. Any idea if it is probably still okay?

For the screws, would something like this work okay in the soil? Would you recommend anything as a lining outside of the fiber blanket?

Thank you so much. Super duper helpful.