Dead mouse

Try odoban. Use it for lots of things and works very well

If the carcass is gone, bleach.... straight bleach ... and lots of it. Pour it on and just let it sit. After it dries up, then wipe of any residue. Been there, done that!

Rent Ozone machine form Home Depot.

Run an ozone machine in the house while unoccupied.

It took us over a year to get the smell out of my Wife's car after it sat in there for a month while we were on vacation. Even took it to one of those fumigating places. Coffee grounds were suggested, Fresh Wave and we tried other things suggested online. Mostly time allowed it to go away.
Do a Google search.

Get some spray from the pet store that eliminates urine odors.

Open doors and use a fan then spray Fabreze
on to the surfaces .
Even then you may have to do it over or wait
till it goes away .

It only takes a couple weeks for them to dry up and the stink will go away.