Struggling with my mums carers

This is a dreadful example of home care, I'm so sorry for you both.
Does your mum have a social worker you can report this to and talk to?

In Scotland all care professionals have to be registered with the SSSC - not sure where you are, but there may be an equivalent if you’re elsewhere in the UK.
Regarding meds - has your mum got a blister pack? That might be helpful, if the pain meds are additional then could you liaise with the chemist to have them supplied in blister packs so that they’re a timed/accounted for medication? That way if they’re not administered then the meds are still in the packaging.
Is it a private company supplied via the council? There may be more than one company for your area - so you could request a change?
Agree with other posters, everything should be in writing, email after every infringement. Ultimately the care commission is the governing body, but in order to have your concerns taken seriously I’d be inclined to go through the process of writing to the company, escalate to local authority, SSSC (or equivalent) before going to the care commission.
Highlight the security issue with the keypad, the hygiene issues (if it happens again please take pictures), medication issues. Ultimately your mum’s rights and care are paramount and should be taken seriously - this company sounds severely lacking.

unfortunately this not unusual.
who pays for this care.
does your mother have capacity.
sounds like it needs to be a different agency.
they should remove all used items, bag them up securely tied, and place in outside dustbin. that is basic.
and of course they should leave the room and surroundings clean.
the whole thing is wrong, as you know.
is there a care manager, from local authority or NHS.
you need to make a formal complaint in writing/email.
detail each point briefly.
emphasise lack of hygienic practice.
i wish you well.
is there a carers' centre near you. they can advise.
good luck.

Is there a government or licensing board that certifies these “carers”? I would report them right away. Document dates and times particularly in regards to your mum’s direct care. This should be in writing. Send as copy to her doctor as well. Although there are issues of abusive actions toward you, concentrate on the care your mum is receiving. Also be sure to mention the deplorable handling of contaminated dressings and/or linens. This is elder abuse in its worst form.