Contradiction with Acts 20:20
Paul's open teaching 'publicly, and from house to house' contrasts with focusing on greeting a specific church in Romans 16:5.
Acts 20:20: [And] how I kept back nothing that was profitable [unto you], but have shewed you, and have taught you publickly, and from house to house,
Contradiction with 1 Corinthians 14:33
Describes God as not the author of confusion, contrasting with the possible confusion of differentiating churches in Romans 16:5.
1 Corinthians 14:33: For God is not [the author] of confusion, but of peace, as in all churches of the saints. [confusion: Gr. tumult, or, unquietness]
Contradiction with Galatians 3:28
Promotes unity of all believers in Christ, whereas Romans 16:5 highlights a specific local church.
Galatians 3:28: There is neither Jew nor Greek, there is neither bond nor free, there is neither male nor female: for ye are all one in Christ Jesus.
Contradiction with Ephesians 4:4
Emphasizes there is 'one body' of the church, contrasting with the specific 'church that is in their house' mentioned in Romans 16:5.
Ephesians 4:4: [There is] one body, and one Spirit, even as ye are called in one hope of your calling;
Contradiction with Philippians 2:3
Urges to consider others above oneself, contrasting with singling out a specific house church in Romans 16:5.
Philippians 2:3: [Let] nothing [be done] through strife or vainglory; but in lowliness of mind let each esteem other better than themselves.