Father Michael Oswalt had his initial six year formation at Mundelein Seminary in Illinois and was ordained for the Diocese of Rockford. In 2009 he left that diocese (IDK exactly how long this was after his ordination, but not many years) and affiliated with the CMRI. After a period of additional formation he was "re"/"conditionally" (IDK how it was presented) ordained by Bishop Mark Pivarunas, CMRI. There was a monastery in Alabama that had a "traditionalist orientation" (for lack of a better phrase, I'm not making a point), but when the abbot died the community and its assets came under the control of the local diocese. There was considerable discussion about that on this forum. The CMRI made a local Mass available to those in that area, and I believe this was one of Father Oswalt's first assignments with the CMRI, while serving a broader geography.
I assume he his still affiliated with the CMRI, though that suffix is not shown with his name. I also do not know what health insurance the CMRI is able to provide its clergy and religious. Regardless, this is very sad. Father will certainly be in my prayers, and if fundraising is needed for his treatment I hope Matthew will be able to provide that information.