Yfwd is the same as a YO and it does make a hole as well as increase a stitch, which is offset by the k2tog dec. You knit 1, bring the yarn to the front, then k2tog and that makes the YO. Or you could just k1, wrap the yarn around the needle as if you were knitting a stitch without the right needle inserted into a st on the left needle, then k2tog.
The thumb method could be the backward loop CO, or the thumb variation of the Long tail CO. I don't recommend the loop cast on for that many sts, it's very loose and messy to knit into on the next row. Try any other method instead.