Warum Christian Allaire während seiner Buchtour ausschließlich indigene Designer trug  

(Alternatively, for a more formal tone:  
Warum Christian Allaire auf seiner Buchtour ausschließlich Kleidung indigener Designer trug)  

*Note*:  
- The phrasing can be adjusted slightly depending on context (e.g., "Buchpromotiontour" for "book promotion tour" if emphasis is needed).  
- "Indigenous" is translated as "indigene" (adjective) or "Designer indigener Herkunft" if specifying heritage is preferred.  
- German often uses the Präteritum (trug) for written narratives, but Perfekt (hat getragen) would also be correct in spoken/casual contexts.
Die wachsende Beliebtheit von festem Parfüm  

*(or alternatively: "Der wachsende Trend zu festem Parfüm" for a slightly more idiomatic phrasing focusing on the trend aspect.)*  

**Explanation of choices:**  
- "Growing Popularity" → "Wachsende Beliebtheit" (direct translation) or "wachsender Trend" (if emphasizing the trend).  
- "Solid Perfume" → "Festes Parfüm" (standard term in German for non-liquid perfume forms like balms or wax-based scents).  

Both versions are correct; the first is more literal, while the second sounds slightly more natural in German marketing contexts.