It is a bug in general, its happened a while back when some of us would use a taser on admins with god mode. It takes away their god mode and also allows them to be arrested.
Although the player did falsely want you so that would be a rule break I imagine, so they wouldn't refund you most likely, not to mention that the tdm arena is a non rp area.

It'll be quite controversial because I am pretty sure that rules still apply in the TDM arena, but you cannot validly rp there due to there being no access there for users, but if the rules are still upheld in the TDM arena which would be the smart thing, then you can get refunded due to many people getting refunded for when they were tasered in their evo suit and got refunded,

Just because you can't rp in a specific area of a map, does not mean that makes anyone within the area exempt from the rules.