Not necessarily. If the contract with Indosat is for the World...

Not necessarily. If the contract with Indosat is for the World Cup only then you are right, but TV2U would take their time crafting the announcement, because it will have some ripple effects. It could explain why Indosat was holding on the signature, waiting to see if they will be granted the license. If the contract is beyond the WC, say 3 years, then this is a setback but it may not affect the whole deal. The WC would have been a nice to have but doesn't change the whole scope of the deal. TV2U may not announce anything until the contract is signed.

There is something else. FMA was granting a single license for mobile operators in Indonesia. That also explains why so much effort was invested in the development of the software, i.e. to show FMA that Indosat had the capabilities. Nevertheless, the license has now been granted only to Telekomsel (FMA explains why in the announcement). Hence Telekomsel's claim to 'exclusivity' during the joint Telekomsel FMA announcement.

Hopefully, Indosat anticipated this and has a backup plan, like find another partner, in Singapore for example, through their Singapore subsidiary, or like what Ooredoo did for other markets. If they don't, the this is it as far as the WC!

The exclusivity part is in almost every announcement for the last couple of days, including in the Telekomsel page you posted (two paragraphs later). Another example below (they all quote the same source anyway):
"World Cup channels can be enjoyed through MAXstream, exclusively only by Telkomsel subscribers using Telkomsel's internet service, starting from June 1, 2018 with various series of Pre-World Cup and Pre-Friendly Matches World Cup programs."
https://selular.id/2018/06/nonton-piala-dunia-bisa-kapan-dan-dimana-saja-pakai-aplikasi-maxstream/

As always, just my opinion!