The 22-year-old will make his Crusaders debut in the match against the Chiefs in Christchurch on Saturday night, five months after the District Court in Hamilton fined him $750 and discharged him without conviction for the assault in July.
The Fiji-born back had initially signed to play with Irish side Connacht last year, but the club tore up the contract in the wake of the court case.
Robertson said he had "never" had any concerns about Reece, who was called into the Crusaders' pre-season camp after being spurned by New Zealand's other four Super Rugby franchises.
