Yes frontline is technically not a roulette. It isnt actually called a roulette in game, it's called daily challenge or something like that. However it is grouped together with every other roulette and like every other roulette gives a daily bonus. Calling it frontline roulette is easily understandable for every honest person and only dishonest people will try to split hairs on this.

I am in favor of giving daily frontline a buddy in daily rival wings. It's an okay game mode that unfortunately suffers from having been literally dead for so long now that it's hard getting matchmaking for it going again. Previous to rival wings becoming temporarly unavailable there was a PF on my DC every friday calling people into hidden gorge and it lead to pretty quick queues. I havent seen them since the reintroduction sadly so a daily rival wings could do a nice job jump starting the game mode again.