I won't deny it is overpowered, but your definition of what is cheating is lacking.
All they are using is tools given to them. The fact this is breaking Onsal Hakair is not cheating, it is a clever use of tools (even if unfair / overpowered).
Cheating would be going under the map and capping the point from there. Exploiting would be figuring out a way to be quasi-invincible via bug-using (for example, become untargetable). Whether Cover could be considered the latter is something up for debate.
By proxy, no - Paladin players currently using this tactic should NOT be banned for what was their toolkit being cleverly used.