Would one expect Canadair CL-215 or CL-415 planes to be equipped with a working ADS-B transpoder?
Military operators can request that their aircraft are not shown on flightradar24.

Operators of private or sensitive aircraft may request their tracking details be restricted or not displayed. Generally, aircraft requesting that they not be displayed on Flightradar24 are military aircraft.

From: https://www.flightradar24.com/blog/whats-this-plane-doing-answering-recent-frequently-asked-questions/
Whether or not an airplane is equipped with ADS-B is entirely up to the operator. Both the CL-215 and CL-415 were designed before ADS-B existed. However, if the mission demands it, ADS-B capabilities may be retrofitted to existing aircraft. Whether this is the case for these particular Canadairs, I do not know (I expect not), but regardless, it's impossible to make any definite conclusions based on the absence on FR24 and related tracking websites.