This will be referring to recently introduced laws essentially banning all/any abortion to be carried out (in some states even in extreme cases like rape/incest, or to save the life of the mother), but outside of that an illegal abortion might be due to it being done later in the pregancy than is legal, or without following required processes e.g. requirements to get scans first, alert the father, or have a consultation (most of which are often just traumatising anti-choice measures). Also as you say, using an unlicensed practitioner or unsafe method, yeah. Which aside from money, is sometimes due to fears of repercussion from their community or partner about either the pregancy or getting an abortion, so they seek back-door options or try to do it themselves without proper care.

She took something that aborted the baby in the third trimester(28 weeks), well after Nebraska's 20 week window for legal abortions. 6.5 months into a 9 month process.

The baby could have survived if delivered, with specialized care, which puts it well outside of the "clump of cells" argument.