If CanadianGolden doesn't reply to this and you're asking if international students (not US citizens or permanent residents) are eligible for funding...maybe. PennVet's dual-degree program is funded by an NIH MSTP grant that they share with the med school. The MD/PhD program at Penn does accept international applicants, although the NIH MSTP grant can't be used for international students. So international students are usually granted one or two slots in the MD/PhD program with funding from outside sources. You'd have to ask Penn Vet about whether they have such slots/funding.
AFAIK, Penn is the only one funded by an NIH training grant...so the dual-degree programs at UC Davis, Cornell, etc. might already be funded in a way that treats international applicants equally. If your fiance is in CA, you're probably looking at Davis. Definitely email them directly to ask about international student funding. 🙂