This is not 5 players for 4 positions.
Bell is not competing for LF or RF playing time. His 5 games a week must come at 1b or DH. And realistically, his bat must be in the lineup every day. Scratch him from your scenario, other than any DH time reduces opportunity for the other 4..
Conversely, none of the other 4 factor in 1B playing time. Wallner, ERod, Larnach, and Martin are competing for RF/LF and DH...if DH is never covered by Bell, Buxton, Jeffers, or Caratini. Lets say 6 games, 12 OF spots avaliable per week and 4 DH spots--total of 16. That leaves 4 starts per week, if you let all of them switch between RF and LF willy nilly and minimize others at DH. Realistically, though, they're not going to put Martin in right. Probably not putting Wallner in left, and I have no idea what flexibility there is with ERod...all of which further complicates getting even 4 starts per week.
All 4 are taking up 26 man spots, leaving 8 to cover CF, 3rd, SS, 2nd, and 2 catchers. You have in effect 2 bench spots left.