I have never seen neon tetras (or really any fish other than large cichlids) bother otos. Most fish seem oblivious to them.
When otos are first purchased, they are usually starved (often, starved to the point of death). So your otos may have been all over your tank because they were extremely hungry and thrilled to finally have some food. However, after awhile, their hunger drive normalizes and the amount of food decreases (they ate it all) so they calm down a bit.
In the beginning, they're also scared so they may dart quickly from one place to another when another fish or person comes by, but after awhile, they adjust to their environment and calm down.
As long as they're active at all, they should be fine. It's not unusual to see them resting on a leaf or hanging on the side of the glass. They should have nice rounded bellies. When they do eat, they have a cute little wiggle. If they're eating in between rests and coming to the zucchini (usually after it's softened), then they're fine.
However, if they almost never move, are breathing hard, have clamped fins, have spots, fuzzy areas, or are laying in the substrate upside down, then it's time to worry.
Otos have a high mortality rate the first few weeks, but after that, they're usually pretty hardy. I wouldn't worry about them if they've just calmed down a bit. What you're probably seeing is a good sign that they're feeling relaxed and comfortable in your tank.
Vicki Rena Filstar pimp #142 (four XP4s/three XP2s/one XP1) Eheim pimp #301 (Pro II 2128) Victor pimp #27 (VTS-253B-320)
90g - Journal
Pelvicachromis taeniatus 'Moliwe'
75g - Journal
Pelvicachromis pulcher 'Lagos Red' Better Pics 8-24
29g - Journal
Pelvicachromis pulcher 'unknown' --
29g - Pelvicachromis taeniatus 'Moliwe'
5g - RCS colony
2.5g - Journal