Published list

Thirteen types on the Windows page. MOBI is not one of them.

TypeNote from the help pages
PDFIncluded for an adjustable layout. Print-format PDFs can be written on directly on Kindle Scribe. USB-loaded PDFs do not take handwriting.
DOC / DOCXInk drawings can fail conversion. In Word, comments become Kindle footnotes for “Like a Kindle book” and hide for “Like a printed document.”
TXT / RTFTXT is treated like other adjustable-layout documents. RTF is on both the Windows page and the help list.
HTM / HTMLBoth appear on the Windows page. The help page writes them as .HTML and .HTM.
PNG GIF JPG JPEG BMPListed as personal-document images. JPG and JPEG are one image family on the help page.
EPUBOn the Windows page. Handwriting is not supported in EPUB comics, manga, and children books.

The 1.1.1.260 installer still registers AZW, MOBI, PRC, and PSZ. A registered extension is not the same as a format the Windows page tells you to send. EPUB, HTM, and HTML are on the page and are absent from that installer list.