Honestly, do your best new guy. The old guy doesn't seem remotely interested in her romantically. There's really almost zero romantic chemistry between them, he's just a wholesome good guy.
And I don't really like "age-gap" romance, at best it doesn't really add anything other than unnecessary drama that doesn't matter in the end, since they're gonna end up together anyway. At worst it's downright creepy and gross. Also it always makes me think "the old one is gonna die years before the younger one, if they end up married."