Ah, oh yes. I see. In fact they don't even need to tie for us to get a choice of which of our party goes first, they just need to be next to one another in the combat queue. Which can sometimes make it helpful to knock out an enemy separating two of your party in the queue as then you have more flexibility in what you do and in what order

You made me realize that the problem is much worse than I thought.
When companions are next to one another in the queue, not only you can indeed select them in any order for their turn in the round, but you can continue to swap between them until all their moves, actions, and bonus actions are completed!
The former would have been bad, but the latter is much, much worse. It's not really D&D anymore but an adaptation of D:OS action point combat.

I hope it's a bug but it looks intentional. If that's the case, I'll continue the game for the story, but I'm very disappointed in how they messed up with the ruleset.