I think both things are affected from your succes(fansurvey), but it isn't the main faactor in merchandise.
Impact on merchandise comes from:
- bonus for players of your nationality
- bonus for players created/drafted in your team
- bonus from nationalteam performances of your players
- from the individual salary of a player, and his stats and playing time (at least the salary is my theory, the stats are stated from the BB but the impact isn't that big)
Your team have only two players from your own nationality, and pays low salary so a relativ low Merchandise is normal.