(How) To show interest in this case?

Hello ladies, I would appreciate an objective input on this situation. I am trying to decide whether and how to show my interest in a guy. Sorry for long specifics…

There are 2 specifics to the story:
1. The guy comes from a country that is notorious for men not flirting or making the first move. So the “if he likes you it will be obvious” doesn’t apply here due to the culture he grew up in. It’s almost impossible to tell if a guy is interested
2. He’s a professional athlete in a sport that’s semi-popular in Europe. Problem is he definitely sees me as a fan.

I met him 2 years ago after a game. I thought he’s pretty cute but that was it. I moved out of the country and when I moved back a year later I met him at a meet and greet. Upon signing a card for me he referred to me by my name. The thing is I never told him my name; presumably he checked my instagram a year ago when I tagged him in a photo. Still, it felt kind of weird that he remembered me after a year.
Since then I commented on his story and DMed him every now and then when something big in his carrer happend. Until recently he always replied in a timely manner, but answers were mostly short. On one hand I was among the selected ones to whom he answered, on the other hand he wasn’t encouranging conversations to continue.

I was recently working at the championship he was competing in. He always greeted me and we high-fived every time his team did well. He even greeted me after my country kicked his team out of the competition and I was wearing the jersey of my team. After another game I asked him if I could have his jersey (he was the best of his country, and employees asking for memorabilia is fairly common at championships) when we return to the country we live in as they can’t hand out stuff before the end of the competition. He told me to text him again about it. I did before his last game (in another city) and whished him luck. He never opened the message.

During the chapionship I was almost sure he likes me, but after ignored message obviously the certainty disappeared. I have no idea whether he noticed that I like him as a guy. His teammate figured it out, no idea whether he told him.
I work at the games of his club (not employed by the club directly) now too, so I can have contact with him after games.

In the looks department most girls say he’s not really attractive , I obviously disagree. He doesn’t have huge female following, but I guess a few girls are interested. Guys in that sport get some attention, but tend to be down to earth. As for my looks, guys whose type I am consider me hot, others evaluate me as average.

My question is should I write this off as a fan fantasy or I should I make my interest clear (and how)? Based on his culture, I believe he won’t make it clear what he thinks about me without me doing something about it. I might be leaning towards better being shot down then kept wondering
Thanks