Louie tried not to think much on it. How he was always the one who ended up getting enslaved. True, it had only been twice now- once with an undead mummy, and the other with something much, much worse- but in such a short time, it really was striking.
But, still, he couldn't let it effect him. He's a McDuck, and therefore he's rich, and rich people have these worries. Ultimately, it might even be in his best interest to have established Doofus as his sworn enemy so young, if only because he has plenty of time to learn the ins and outs of beating him before he obtains the money Scrooge is bound to- will hopefully- leave him.
Maybe it worried him more that Doofus and Toth-Ra both hadn't harbored any interest in gold, or riches, or power. They'd had it all already. Toth-Ra had been a suggestion, an unraveled moment of desperation; Doofus hadn't been his idea. Doofus had wanted him, plain and simple, in his own twisted, weird way. He wanted all the friends he could posses, but Louie had been the first in duck-knows-how-long to approach him willingly.
It finally occurs to him when he puts on a necklace and immediately felt choked that maybe he had a problem. And maybe, in his haste to rip it off, he'd slipped right into the pool, but Louie's a good swimmer; rather than panic, he's simply annoyed, yanking at the gold he had once loved so dearly until it finally broke. It slipped from his fingers, landing on the pool bottom with an inaudible clunk.
Louie burst free from the water, soaked and humiliated, and resolved to never let this sort of thing happen to him again. No matter what, he would always be free.
If they thought they could contain him, then the joke was on them.