To create a regex that matches the 6 specific target items while avoiding distractors, I'll create patterns for each item and combine them with the OR operator (|):

1. Email: `user\+tag\.name@example-domain\.com` 
   - Escaping the plus and period characters which have special meaning in regex

2. Phone number: `\+1 \(800\) 555-0199 ext\. 123`
   - Escaping the plus, parentheses, and period characters

3. Date: `2020-02-29`
   - No special characters to escape

4. Special code: `SN\/2020-AB\/XY`
   - Escaping forward slashes

5. URL: `https:\/\/sub\.domain-example\.com\/path\?query=value#anchor`
   - Escaping forward slashes, period, and question mark

6. Padded email: `   complex_user_007@example\.io   `
   - Including the exact spaces and escaping the period

By combining these patterns with the OR operator, the regex will match exactly these 6 items in the text and nothing else.