There is indeed a distinct visual difference between it and Papalymo's, and that's the lack of the sigils associated with the Twelve in the latter. This, after all, is what Louisoix's looked like:
Papalymo's has the sphere that forms around Bahamut initially, but it stops there. What I take this to mean is that Louisoix used his half-summoning of the Twelve to bolster a pre-existing sealing spell, which Papalymo used on its own. Of note, that spell isn't what took Louisoix's life, so Papalymo may not have sacrificed himself after all; then again, there are any number of ways the circumstances could be tweaked to require the life of the caster this time around.
Kinda throws into question Ilberd's claim that his Primal - whatever it may be - is stronger than Bahamut, too.