No, but, thanks for the interesting Howarth and Jacobson article.  Whatever the GHG emissions are from "blue" hydrogen production, they are in addition to methane emissions from gas production and processing activities.

The data I quoted are from the EIA and discussed in Energy Central here.  The factor of "28" was used for the multiplier of the GHG effects of methane compared to CO2.

In part:

But, using the estimate from EIA, at 1.28 billion cubic feet per day¹, that is more than 25 thousand tons of methane per day and over 9 million tons of methane per year., With a greenhouse warming effect of 28 times that of CO2 (conservative minimum over 20 years) that equals 261 million tons of CO2 per year². The article states “Since 2005 (through 2020), the U.S. has reduced its CO₂ emissions by 970 million tons.”

So, in just one year, methane emissions from venting and flaring negated more than a quarter of the claimed reduction of GHG emissions from CO2 since 2005 as a result of replacing coal with natural gas. At this rate of flaring and venting, the net emissions of GHG from just Texas and North Dakota gas will negate many times over the reductions quoted in this article. 

The argument becomes stronger when one takes into account the Texas Railroad Commission`s numerous "exceptions" to the rules about flaring and venting which are "off the books", as well as methane from wellhead leaks, liquification and revaporization (where applicable), transferring and pipeline operations.  One proprietary and conservative estimate of methane losses from "conventional" (not fracking) gas production, treatment, transport, transfer is 6-7% of production. After all, operators meter quite accurately (multi-phase metering) gas produced, gas burned in processing (removal of water and recovery of anti-freeze) and gas delivered. Where do you suppose the rest goes?

Further add emissions from abandoned wells.  There is great uncertainty in these estimates. One study suggests:

"We estimate the number of abandoned wells to be at least 4,000,000 wells for the U.S. and at least 370,000 for Canada. Methane emission factors range from 1.8 × 10^–3 g/h to 48 g/h per well depending on the plugging status, well type, and region, with the overall average at 6.0 g/h. We find that annual methane emissions from abandoned wells are underestimated by 150% in Canada and by 20% in the U.S. Even with the inclusion of two to three times more measurement data than used in current inventory estimates, we find that abandoned wells remain the most uncertain methane source in the U.S. and become the most uncertain source in Canada."

That range of uncertainty is enormous (1.8 × 10^–3 g/h to 48 g/h per well). So, nobody really knows whether it´s hundreds or hundreds of thousands of tons per year.