Giertz did live in her native Sweden until 2016, but she now lives in these United States.
Her citizenship is not mentioned in Wikipedia, so her health insurance coverage may be a matter of private, personal funds, because she probably has neither Medicaid nor FTE with benefits.
I got the impression that she had the surgeries in the US and that she was employed at Adam Savage's Tested at the time.
Therefore, I had always supposed that her employment would have involved health insurance.
If she had gone back to Sweden to do it, the surgery would have been free but she would first have had to reestablish herself in Sweden and then struggled with waiting time for her first doctor's appointment and possibly multiple referrals before she would have been put on a waiting list for surgery ... during which time her condition could have worsened. (I live in her old home town and have gone through something similar...)
If she had been diagnosed at a hospital in the US she would already have been in its system and would probably have been put on its priority list right away.
Her American accent always amazes me. You'd never guess she was making Swedish content in Sweden until only a few years ago.
I would hope she has health insurance. Whenever I was self-employed I still made sure I had a private plan of some sort, and she has a whole company with employees, so it would be pretty easy for her to get a group plan.