Inter-market curve strategies

Vol 4 Reading 20, Example 4 (page 181),

in Sol 2 it says "In addition, the 2-year bond offers a higher spread over the German bond (5.87% for the 2-year versus 5.48% for the 10-year) and the EUR swap (5.36% for the 2-year versus 5.12% for the 10-year). "

I don’t understand what’s the relationship between the Greek gov bond yield and German bond yield/ EUR swap rate. Does the German bond yield and EUR swap rate depends on the Greek bond yield? The question asks for the pros and cons for Greek bond, so why a higher 2 year spread for German bond and EUR swap an advantage for Greek bond?

Any comment is appreciated:)

Solution 2 is exploring relative valueness of the Greek bonds by comparing them to their respective German bonds and EUR swap rates, and isn’t so much about causal/ pricing relationships per se.

Hope it helps.