I haven’t heard of any experience with the cases involving your situation, you might want to search through other immigration forum sites. But I can offer a comparison. I used to have H1B and had applied for GC. I got a visa stamp when I was in Nepal and they could clearly see that I had applied for a GC, that means I have every intention of not returning back. I think I should have had a bigger concern than yours since it was me directly involved, at least in your case it’s your folks. The interviewer didn’t ask me any question other than how the weather is up there now-a-days and stuff like that.
I wouldn’t be too worried, but just to make sure do some searches.