They do look like abrasions to me, but keep a close eye on it because bacterial infections can become a problem due to their soft tissue.
Stick with gutloading ghost shrimp until you wean him onto prepared foods. Until then, go easy on the krill as it has shown negative effects in predatory fish when exclusively fed. Shrimp, squid/octopus, silversides, crab, etc can be offered and all can/should be injected with supplementation (selco, etc). I'd also recommend a feeding stick (rigid airline tubing works well) and try to coax the lion into thinking the food is alive (may take several tries).