The blog is correct that gravity can shift the wavelength of light. However, it doesn't seem to do any calculations of the redshift we see is compariable to what we get from gravity. Plus, you wouldn't get a linear relationship (d=H*delta v) that we see because there is a limit on how mush a given source can shirt the wavelength.
This blog is ignoring all the supporting evidence for the hubble constant and the expansion of the universe that has nothing to do with shifts in wavelenth. Link
This blog is ignoring all the supporting evidence for the hubble constant and the expansion of the universe that has nothing to do with shifts in wavelenth. Link