"Open for gifters in Unlucky-7"

No, it's completely irrelevant for you if you're not a part of that group. I believe the gifters in that group can only join giveaways that have that description, so putting it there is necessary even if it's a multi-group giveaway.

Being part of that group, I can confirm the statement above.
Basically, it's a group meant to facilitate winning for people with 7 or less wins, where after the 8th, we should either leave or become gifters.
Gifters are those who are there mainly to make giveaways, they usually can't enter them, unless the giveaway creator state so (and even then, there are special rules about that).
If a giveaway is multi-group, that statement simply doesn't apply to you, so you have nothing to worry about.