I have had lions die unexpectedly while thriving and doing well. 2 years is a little longer in my experience but I would imagine still possible to have some of the same possibilities. Exposure to meds seem to effect most after a year or so, that would be copper and antibiotics specifically. Copper is almost a certain death sentence. I've never seen any lion live much more than 1.5 or so coming from sources that run copper in their system or ones that may have survived a treatment.
Repeated antibiotic treatment seem to have a similar effect. Many lions come in with cloudy eyes and bacterial infections, and early on I followed shoddy advice from the so called lion experts and treated with antibiotics, most of the time followed by another treatment. Inevitably these lions would last a year to a year and half, seemingly doing well, then just stop eating and die. I learned that unless the bacterial infection is bad, it's best to keep optimum water quality, feed well, and watch closely. Best results, lions now live for years.
The sudden death is likely organ failure, think of it in human terms with the effects of drugs on the liver and kidneys.
Bloat is another thing that happens, which is a result of being overfed. I doubt if 2 small mollies would have done it, but it would depend on the size of the lion and the size of the mollies, and when he was fed prior. If that happened, shortly after feeding he would likely get lethargic and very inactive for the next couple days or until he expired, with a very huge bulge. I feed live to 3 tanks with multiple preds and it's difficult sometimes to make sure someone isn't over indulging. I have to use a rigid airline to fend off my yellow fuzzy from eating the rhino's food.
My lions and scorps have been eating mollies for several years and are thriving. There is a very low if any chance for internal parasites from mollies to affect a lion. The freshwater parasites are easily dispatched by the lions gut, if healthy. There is a procession that takes place with internal parasites, and it doesn't happen overnight. 1st their appetite would become insatiable, you would likely then see stringy poo, then the lion would stop eating; this can take as long as a couple of months. Even if you missed all the signs it would take a couple of weeks or more after they stop eating.
The high risk would be to feed any saltwater fare without qt, that includes inverts since most places stupidly keep fish with their inverts. People that continue to warn feeding mollies and fresh water ghost shrimp, which are actually a variety of shrimp that live in fresh, brackish, and salt; as do mollies; have likely never kept a true predator fish more than a few months to a year at most.
Very cool line up btw!!
