The player's agent, Viktor Kolar, and his company have invested a lot in the young shot-stopper.
"It's a milestone for me that such a sum of money was paid for a goalkeeper," Kolar said in an interview with the Livesport Daily podcast.
"The Czech league is still not perceived in a way that Premier League clubs pay big sums for local players."
In the summer of 2021, when Kinsky was moving to Slavia from Dukla, you said the club's demands and the quality of his teammates would help him reach the next level. Your words were: 'In our eyes, he is clearly a goalkeeper for European football'. Has that now been confirmed with the move to Tottenham?
"The fundamental thing is that, in Kinsky's life, few things have happened and are happening by chance. He has always set himself goals and plans. Moreover, he consulted his family on all his travels, with his dad playing a major role.
"And I must say that Petr Cech was also an inspiration and motivation for him to work on himself. This was the basis for his extremely hard work, attitude, behaviour and thinking.
"Kinsky was always interested in going abroad as early as possible at a young age - and getting into the best competitions, the best possible club, where we would have a real chance to work hard."
Jaroslav Tvrdik (Slavia's chairman) publicly declared that club management initially preferred another offer - it was smaller, but Kinsky would have stayed on loan in the Czech Republic and would not have left until the summer. How much did the fact that Tottenham got in touch crash that?
"We originally planned the transfer for the summer, but we wanted to be prepared that something could happen in the winter. We have been in contact with many clubs from different leagues since the summer and we have told more or less everyone that the ideal time for Kinsky's transfer is after the season.
"But then Tottenham came in and made a frontal assault between the holidays. They presented a model to Kinsky, to us, and to the whole family, of how it could all work."
They needed to get a goalkeeper urgently, didn't they?
"The fact that (Guglielmo) Vicario got injured helped. When they presented to us how well they know Kinsky - how his way of playing suits Tottenham's game and their style of play, the kind of football Ange Postecoglou wants to practice - we became convinced that it was the right move.
"Already, the club has shown that Kinsky has made the right choice. There were other options, but there is only one Premier League. Moreover, Tottenham is a club that is perfectly set up."
In what, exactly?
"They've worked on the infrastructure for a long time. Today, they have the best training centre in the world, a top stadium, they hire quality staff, and they have excellent facilities and equipment. The technical support is at an all-time high, so all that's missing now is to transfer all that to the pitch."
Recently, they have been investing in young players. Was that also one of the reasons for the decision?
"Daniel Levy has been a guarantor of the club's long-term support for young players. We have known each other for a long time (and) have done several transfers together - back in 2008, for example, striker Roman Pavlyuchenko - and I know very well that he promotes young players. Just look at who is playing and how old they are. Kinsky has all the conditions to adapt quickly, confirm his qualities and develop further."
There are several reported transfer fees floating around. There is speculation of £13-15 million euros. Can you confirm whether the true fee is actually in that price range?
"The amount is many times higher than the most expensive transfer of a goalkeeper from the Czech Republic. Overall, it is close to the most expensive ever sale from the domestic league (which is Tomas Soucek, who in 2020 signed for West Ham in a deal worth around £17 million - ed)."
Do you see this as an exceptional feat in that respect?
"It is a milestone for me because the Czech league, abroad, and certainly not in the Premier League, is still not perceived as a competition from which top clubs should buy for larger sums.
"Tottenham were yet another club that we talked to for whom the confirmation of Kinsky's qualities were his games in the Europa League and for the national team. The Czech league meant nothing to them."
Moving on, it is a large sum for a goalkeeper - that is not usual either, is it?
"Clubs generally always want to pay less for a goalkeeper. The strikers are usually higher on the priority list, and they already spend more for them. There's a perception that buying an expensive goalkeeper is a risk, because either it's going to work or it's not, and then you're not going to get an expensive goalkeeper.
"But the people at Tottenham trusted Kinsky. The whole scouting team, which has 11 other people in addition to (head of scouting) Rob Mackenzie, agreed on one of two names in the vote."
Can you reveal what Kinsky discussed with Petr Cech when they discussed the transfer?
"It was mainly goalkeeping matters. They consulted how things work in England; how the warm-ups before games are done, how to time the schedule, what exercises to include and things like that.
"Kinsky really appreciates it because Petr is a great motivation and inspiration for him."