Well you certainly have the pets for it
One way to get this would be to either build a scary OP team and scare away opponents (especially if you PVP late at night so get the same guys coming back) something like a Murkalot/Fossilised Hatchling/Mechanical Dragonling that takes big chunks out of teams quickly before any of your pets die, or outright kills them.
Another way would be an "unkillable" team of healers/tanks, like Blossoming Ancient, Sunflower, Crawdad teams.
If you have a friend, you can use a weird matching lvl combo (like lvl20, 4 and 9 pets for both players) to ensure you meet each other in random PVP and can have them forfeit for you.
And you can forfeit before your pets die multiple times and still get the Achievement in the end...
I found it was when players ran away in fear/frustration repeatedly that I could get this at lvl25, felt cheesy but I didn't refuse it.