Question: Unfertile male? Something else?

Okay it's weird to put anything in the Sick Axolotl section because luckily my lotls haven't been sick for a while...... yet.

But I've said this before. I have 3 females and a male. The females look awesomely round. 2 of them look like their gravid for 342 months. But nothing happens.
Okay. Maybe it's not the time for them. (Yep, that's the answer I get all the time, but maybe there is something else)

Let me explain it a little better:
I have Xotl (my male) for about 3 years now. I got him when he was a tiny wildtype and even before I knew that he was 'mature' I found spermatophores in his tank. Then I knew it was a dude. There were no other axies or females in the tank but he just loved 'spamming' those things.

Months later he was in a tank with a few others. I've noticed some spermatophores (I call them 'funny jelly things', because I hate to type that word). Oh well. But nothing happened.
Maybe the females weren't mature enough.

But now they are. They're 2 to 2,5 years old. And still nothing has happened so far. I haven't seen 'funny jelly things' for about 2 years now. And I don't know what's the problem. He hasn't been 'lucky' so far. I don't see them doing 'funny dances' at all. They're just couch potatoes.

About 1,5 - 2 years ago Xotl got pretty sick because someone had given me a golden axie but she turned out to have internal parasites and it was too late to save her. She died. Later my other female died (shortly after I had discovered the internal parasites) and Xotl was in bad shape but he survived! (He looks a bit weird since then. Not sure if it has anything to do with the sickness or treatment but he has a lip zit (yep, it's there for 1,5 years already) and one of his gills is long and 'frill-less' and he's a little thin but eats like crazy!)

Is Xotl just an unfertile axie? Or is he too old to 'make babies' (3,5 years)? Does the sickness part have anything to do with it? (I doubt it)
I want to give it a try with another male but I don't have enough room in the tank for another axie and I don't have (large enough) spare tanks left to put Xotl in.

Well. I mean INfertile. (I was probably thinking about 'unfertilized' so my English sucks)

I HATE this.

Take out 2 of your females and put them in a different tank temporarily. Mine hardly ever mated in multi-axie setups, always as lone pairs. Rearrange the tank and do a big water change. That should trigger spawning.

I don't have a spare tank left, so my only option would be a bucket or something. But I'll give it a try

Try lowering and raising the tank temperature and light this generally gets mine to breed.

Thanks.

But is it possible for an axie to be infertile? If yes, does anyone here have or had an infertile lotl?