The pseudo jinchuriki stuff? It should be allowed. Pseudo Jinchuriki abilities are tier 2 as per Sora or tier 3 depending on the gin/kin bros. Which should make it eligible to be a unique ability unless they make up a rule change on the spot.
"Unique abilities are far more diverse, and open in what's allowed for them. With uniques your Summoning animals are allowed to go beyond the conventional boundaries of what's allowed on a Summoning Contract. This includes allowing them access to certain fields within a given scope, allowing the summons access to fields like Advanced Ninjutsu or Elements, or even creating their own unique Advanced Ninjutsu or Element adjacent abilities. Contracts with Kekkei Genkai Unique Abilities are less likely to be approved unless the user and more specifically the Biography using that Contract has that same Kekkei Genkai. In other words, a Contract with a Kekkei Genkai Unique must be summoned by a biography that also possesses that Kekkei Genkai. Dojutsu and Tier 4 and higher abilities are excluded, making them ineligible as Unique's on a Contract."