I think part of the problem was they took a huge hit financially by the 2019 election - they're still a smallish party (region wise, they don't operate through the whole of the UK) albeit their membership was quite high a few years ago (120k-ish). So an unscheduled election in their 5 yr financial cycle wouldn't have been easy to fund. But they've been shedding members since their peak, with a massive exodus when Cherry was sacked (not great timing as they'd already started asking members to pay their dues early) and now with the Alba exodus, I wonder what their numbers are like now.
I don't know how true this is but I saw it mentioned that Salmond's SNP had about 20k members before they got the indyref secured, and it's been suggested he's managed to attract a similar number for Alba party.
In terms of finances, I've no idea what they've done with the Indyref fund as it was raised money for a specific cause. The explanation given was it was mixed through their accounts & not visible in their published accounts. That sounds like BS to me. But I am not an accountant so can't say what all this means.