I can see why level 2 is becoming the standard, if it doesn't you could potentially end up with all the people on an agreement having level 1 but potentially have never shot a deer. I know everyone has to start somewhere and level 1 is better than nothing but by asking for level 2 they know the tenants have at least some level of stalking experience.
I also looked into this the other day on the FC website and the exact wording was that the license holder held DSC L2 with other members also holding L2 then in brackets or to be obtained within 12 months.