OP is talking about CAR-T therapy which is in routine clinical practice. In the UK costs have gone from £600k to around £250K That includes the surrounding medical, nursing and follow up care. In the US costs are likely to be more than that.

The article is talking about a very bespoke process where they take a patient's cancer, sequence the whole thing, select mutations they think will be presented on MHC-1, predict the antigens visible, and 'somehow' (I need to read the article more carefully to figure out how they did this) select a TCR sequence which will bind to that. Then they use CRISPR to graft that onto the TCR gene of a T cell from the patient (3 types by the looks of it), and re-infuse the targeted cells.

So yes, that would cost several million.