Title of the article is "Coyotes would expect taxpayer money for new arena" which is a given. That the 'investors' have anything real to bring to the party is purely hypothetical, and most likely not true in the way other teams have helped pay for arenas.
"Why not invest it in Glendale?" makes zero sense as a question. Contrary to popular belief, owning the arena is not a free to pass to profit land. The optimal setup is to have the city foot the bill while being in a position to either be paid directly for managing the arena as the Coyotes were or to reap the benefits from an event heavy arena.
Both situations are no longer possible in Glendale. It even says in the article why "investors" would be willing to cough up some money for a downtown arena.
The only interesting tidbit is that ASU would join the Coyotes and Suns downtown. That would make three partners in on a facility, and potentially help sell it to the public. It'd also water down the power of the Suns in a new arrangement.
The public having to vote on it makes the timing problematic.