Castlepines Equity is like all other equity firms, they make an...

Castlepines Equity is like all other equity firms, they make an offer, get to the books & a DD. They want a bargain they can make money out of, make & influence decisions along the way with collateral damage is normal. Sell out the remainder of assets & move on.
If and a BIG IF, had Castlepines completed their DD they may not have invested in DML at all, not enough profit.
They may have withdrawn like all others and looked elsewhere.