Firstly, the best way to read the Inspire post is not to get lost in the replies, but to read the post which has enumerated several of the best thoughts in the posting.
Next, let's talk about your calcium; you need to know if you are getting enough calcium. Let me suggest that you look at your dietary intake by using cronometer; they have a simple daily input program that will tell you about not only your calcium intake but most of your nutritional intake. Ck it out; you may not need any calcium supplemention or you may just need a little.
But now in case you do need more calcium you can either go the dietary route or take some supplements.
But I think that you are missing from the research that no matter how you fill your calcium needs if your body is putting that calcium in your cardio system instead of in your bones etc. then you have a problem.
The calcium/cardio problem is not tied to just to supplementation. It is amplified by supplementation. Supplementation only has the potential of making your existing problem worse, attentuating it, as the research says.
That calcium/cardio problem, if you have it, is that your body is not regulating your calcium well and is putting it in places where it is dangerous for you.
Vit k regulates calcium; it is the traffic cop for calcium and puts it where it is more likely to help and not hurt you. The research paper points this out by saying "because some evidence points to health problems at elevated levels.
That issue could be remedied, however, if the right amount of vitamin K2 were to be added to a high-calcium regimen. Vitamin K2 promotes arterial flexibility by preventing accumulation of arterial calcium,10,47,62 and supplementation with it could correct calcium amounts in the body that are out of balance. Thus, calcium in tandem with vitamin K2 may well be the solution for bringing necessary bone benefits while circumventing an increased risk for heart disease."
The recommended dose for mk7 for patients in the book was 200-240mcg daily. Daily recommended amount is more like is 150 to 180 µg per day.
The 200mcg seems to be what you are taking in your NuMedica supplement of D3-5000 + K2-200 (MK7).
Note on the Inspire discussion that many replies mentioned syncopations as a possible side effect of vit k. Because of this many posters obtain their vit k thru their diet as much as possible.
Calcium deposits in your breast may show that you are prone to deposit calcium, but they may just be caused by lots of other benign conditions which have nothing to do with your cardio system.
Still, there is some research connecting the two: https://www.ahajournals.org/doi/10.1161/CIRCIMAGING.121.013526