Aside from aspects that don't make sense for a "sequel" to be extremely likely, there's something major that must be noted that might add to it.
Frontier Developments is a public type company, associated with a stock exchange (the London Stock Exchange), and any contract agreements between them and anyone else would be noted, but usually without noting what kind of IPs or any kind of associated parties they are until the games are revealed. If Jurassic World and Universal Studios was associated with Frontier Developments of making a new game of any kind, perhaps there would be a new contract for them to do so, which makes sense.
After all, in Febuary 2017, they said the contract signage for a Hollywood IP, which would remain a mystery for many months until the game was revealed as Jurassic World Evolution on August, would be involved with the production of one game and subsequent DLCs. Those subsequent DLCs were revealed to be Universal Pictures based (Back to the Future, Knight Raider, and The Munsters), all for Planet Coaster. Frontier won't be able to do this, unless a contract agreement was placed with the association with Universal themselves. This vaguely hinted the new Hollywood based game announced back in Fabuary was Universal Pictures based, and only for one game. As it was revealed, it was a UNiversal IP based game: Jurassic World Evolution, based on the Jurassic IP.
When this new 2021 game was revealed, it was said to not only be based on a "major global IP", but to also come with "associated subsequent DLCs". Because the initial IP securing agreement back in 2017 was only for one Universal based IP, it would probably make sense for Frontier to be able to get another contract agreement for them to make on any more new games.
But...
That wouldn't explain the existence of the Ghostbusters DLC pack for Planet Coaster. Frontier has been associated with Sony as a whole, for the use of their gaming consoles: PlayStation. However, that doesn't mean they have full access to all of Sony's properties. With their only association with them in the past was Sony's subsidiary company, Sony Interactive Entertainment, but never with their other subsidiaries. Frontier would need agreements with those daughter companies for their properties to be legally associated with any Frontier's projects, otherwise it's copyright infringement if they didn't go through the proper legal circumstances to make those game projects possible.
The Ghostbusters IP is owned by Sony Pictures Entertainment Inc., the respective subsidiary of Sony, and a company that Frontier Developments have never had any association with in the past until 2019. The only way for the Ghostbusters based DLC to exist as it does is for Frontier to have a contract agreement with the daughter company, Sony Pictures, otherwise Frontier will suffer from legal issues.
This would mean that Frontier must have two agreements in place for both SP and UP to have both the Ghostbuster DLC and the so-called "Jurassic World Evolution 2". Right?
Well... between the announcement of the new "major IP game" back in early March of last year and now (the time of this post), there has only been one contract agreement in place. Even Frontier's announced collaboration with Haemimont Games, a private type video game company, for the development of another untitled video game, isn't a contract agreement for major IP stuff from other companies to happen. The Ghostbusters franchise as a whole, it should be noted, has never ever been associated with Universal in any way, ever.
How does it make sense for a Sony Pictures based IP based works to exist and a "supposed" second Jurassic World (Universal Pictures) based game to be developed and planned (including that claimed "Jurassic World Survival" game from the series of leaks that happen at last year's Spring) at the same time if only one contract agreement for only one game existed through out this long time span???
If it's a Sony Pictures IP based game, like I believe it is, I do have a couple of ideas of what it could be that which Frontier Developments could possibly go for.