Sorry you are going through this with both of your babies. I'm glad you found YT as there is a wealth of information here.
I would do what the others suggested. When you get the test results back, I would let the breeder know if something does come back positive. Most of them will say none of their others are experiencing the same thing....doesn't mean there still isn't some genetic issue in her/his lines for breeding.
I'm surprised they're not showing a little more concerned about their babies they just sold to you in recent weeks....
I hope everything comes back okay and they have happy, long lives with you!