Having never seen this particular hole, I like the fountain grass idea as it can 'paint' the Winter landscape...then be cut way down in the Spring. Any variety of these takes a few years after the initial planting to really get going...and they need a LOT of sun exposure to grow to their tallest. So, unless this is the South side of this tree, it will provide semi-marginal coverage at best.
Play OPEN sometime. It is TOTALLY WORTH IT to play, watch & learn. DG is very laid back, as are the players...so just pay/invest the $ (same $ as playing a lower division usually) and enjoy yourself while you IMPROVE!