Weasel was starting to smell doggy, but now she's squeaky-clean:
I've bought "replacement squeakers" on Amazon - 20 for $8. Mishka loves squeakers, so I occasionally replace the ones that have died.
I wash plush toys pretty regularly (Mishka has dust mite and mold allergies). Hot, scent-free detergent and through the dryer on hot (no fabric softener!) - if the toy is somewhat beat up I put it in a lingerie bag for both cycles. So far, no cleaning-related squeaker deaths.
Clothes washer. Never had a problem washing those plus dawg toys in the wash machine. If it can sustain Dawg Play, it can sustain the washer.
Soggy squeaker may stop squeaking. Dog doesn't seem to care.