Steel chief executive Sue Clarke said the franchise was not made aware of the Fever camp's concerns in the lead-up to the weekend's game.
"We would be very disappointed to learn of any visiting coach or team being treated in a negative way," she said.
Known for her outspoken style, Plummer has often courted controversy over her coaching career. She got off to a rocky start with New Zealand fans when, after taking on the Australian coaching job, she famously claimed the Silver Ferns played like a "bunch of scrubbers" in the 2003 world championship final.
While her frank and forthright approach has often jarred with the conservative netball set, many consider Plummer to be a breath of fresh air for the controversy-shy sport.
Norma Plummer
• Coached the Australian netball team from 2004 to 2011, winning two world championships during her tenure.
• After stepping down as Australian coach in 2011, she took over the reins of the Perth-based West Coast Fever side in the transtasman league.
• Known for her outspoken style, Plummer has often courted controversy over her coaching career.
• She got off to a rocky start with New Zealand fans when, after taking on the Australian coaching job, she famously claimed the Silver Ferns played like a "bunch of scrubbers'' in the 2003 world championship final.