Iirc they’re really supposed to use 30.42 or whatever as the average number of days per month. Of course if you’re “not there” on days you’re not supposed to work anyway, they can’t count those as missed. I would talk to the labor department (and also mention the missing vacation pay).
Did they grant the required amount of bereavement leave (assuming your job is subject to the LSA), and have they correctly reported your salary to the BLI (assuming your job is subject to labor insurance or supposed to be)?