PLEASE help. Recently deceased friend gifting me this plant for Christmas.

I posted on another sub, but no one has replied. 😞

TLDR-Does this look like spider mite damage?

As per the title, a good friend of mine gifted me this plant for Christmas. Sadly, she passed 2 weeks ago. I have lots of plants, but this one is special and I so badly want to help her thrive. She had quite a bit of mechanical damage when I got her, but she was clear of pests. I did go ahead and quarantine for a little over a month, as I do with all new plants. A few days ago I noticed that a lot of her leaves were looking sad. Brown spots and some badly crisped edges. Her newest leaf, pic number 2, has some weird yellowing toward the bottom. I noticed a bunch of very tiny, whitish colored mites quickly scurrying around the leaves and stems. No eggs or webs or debris, so I am wondering if they are some kind of predatory mite, but the damaged leaves has Mr concerned. I don't want to treat her if we don't suspect spider mites. Does the damage look like it COULD be from spider mites?

I water her roughly every 10-13 days. High humidity. Pot has drainage and substrate is very airy (perlite, pumic, peat moss/coco coir). She sits near a grow light for about 10 hours a day.

Thank you so much for any input you can give me. I really don't want to lose this plant.