If he refuses, issue an arrest warrant and call in the National Guard or the US Marshals to put the feeding tube back in.
Personally think she would be better served to have the Feds step in and put her in protective custody outside the State of Florida.
You can replace a feeding tube back into it's stoma, but it has to be done rather quickly (within a hour or two) before it closes. To place a new one would require a procedure - that would technically require the consent of the next of kin - her husband.
Plus is ridiculous to demand the National Guard be pulled in to do this. Give me a break.