This is a standard procedure that the SEC implements when there is a complaint
that is complete and total nonsense. the sec does not suspend and then investigate. it investigates and then suspends. any further investigation will be to determine possible additional charges.
here is data from the SEC own website. they recieved 3809 complaints in 2021 in relation to market manipulations. they certianly didnt suspend that same amount of companies. so they cant just be reacting to a frivolous complaint as you say. this is the reason they thanked the OSC. they obviously recieved info from them in relation to this to formulate their decision.