Never used lure specifically for otter,but I have caught a couple in beaver sets lured with Bob Wilsons. I have caught a few in boxes baited for mink,but in my opinion blind setting is the way to go for otter if you want reliable results. If I was going to try lure for otter I would go with a fish oil type lure.
I agree with Boco. Although I haven't caught that many, I found that otter don't seem to respond to lure as well as I would have thought. My best sets have been blind sets. .
The top picture a small otter went for duck wing etc in a 120 flower[pot set for mink not sure about the lure. Seemed random. I've caught otter on a hanging duckwing lynx set with castor for lure. Once again seemed random. If they're coming to a toilet, no lure needed. Like others have said, blind sets have produce by far the majority of otter I have taken. Here the go to otter trap is a 280.
Yup with otter its all about placement. Lure is pretty low on the list of things to consider with otter.
If the location (otter toilet or crossover) allows a dirthole set to be made and anchored then lure is all you need. No bait. I have used Caven's Otter Lure Supreme with outstanding results. I have lost count of the otters I've caught in dirthole sets.
I agree with others that blind sets are the way to rack up good otter numbers. At times I tried otter musk as an attractant but found more often than not it seemed to create more alarm than attraction. During the rut in the early spring urine from an estrous female will get those males right where you want them on a sandbar or toilet situation where you are seeing tracks. Otter scats and urinated upon materials that they leave on toilets will also get their attention.
An old timer (that I had quite a bit of trust in) swore by a buried skunk carcass on a sandbar with traps set around it. I never tried it as eventually I learned to find toilets and crossovers blind setting those with good success..