If my opponent has no benched Pokemon, do I do 30 damage to their active Pokemon when I use Mawile's "Invite and Strike" attack?
No, damage is only done to the "new Active Pokemon". If there is no switch, then no damage is done.
Source: Temporal Forces FAQ; TPCi Rules Team (2024-03-21)

Relevant cards

Note: All applicable cards may not be listed below.
SV5_112
SV5_112