These functions in above code snippet need some delay to wait for taking effect after writing to the registers respectively.
Generally, it will take up to 1 or 2 LFCLK cycles to take effect for related different bits of MCWDT registers - MCWDT_CTLx/MCWDT_MATCHx...
The recommended values of delay shown in respective PDL API comments are just - actual required time + 1 LFCLK -
to guarantee the valid function.
However, you can set the parameter - waitUs as 0.
In this case, it is the user's responsibility to check whether the selected counters were enabled/disabled/reset immediately after the function call, or it must be taken into account when changing the match values on the running counters. Bleow APIs might be useful for such considerations.