Vanishing twin and NIPT test

I had an empty sac at my 8 week scan and Iit was still visible at 10+5.

I am being told this will impact NIPT testing as it may pick up abnormalities from the vanishing twin. I am really wishing I could have conclusive answers about the healthy baby still growing. I am 35, have 2 kids and experienced a chemical pregnancy just before getting pregnant with this last baby.

Any words of wisdom or experience like this? I feel like I am basically being told the bloodwork may never come back correct if sac doesn’t go away.