Without a shadow of a doubt Jarwin would stay before Rico. Schultz is far and away the more likely to get bumped to make room for Rico.
Jarwin has no draft pedigree and has shown me nothing. He ran two terrible routes in the Cincinnati game, one of them should have been a TD.
Schultz has shown very little as well (boneheaded decision to NOT go out of bounds before halftime last week) but because of what we invested in him, I'd probably consider keeping him over Jarwin if we can't IR him. I'm just not so sure he'll clear waivers if we do cut him simply because he was a 4th round pick and ranked in the top 5 for tight ends this past draft class (albeit in a weak TE class).
Swaim is my primary in-line blocking TE for more power sets (though I prefer going more 5-man gun lines myself, like the Eagles), and Rico is my slot TE when we go more shotgun.
Thus, if Rico has to block, he's likely blocking a safety, nickel corner or small linebacker, not some big guy that might overwhelm him.