What you are talking about is Henry Hub gas price (US gas price).
While there is a growing trend to link some LNG contracts to Henry Hub, this is largely US LNG facilities - it puts price risk on the buyer rather than the intermediate (LNG facility). The only impact of Henry Hub on WPL is via Corpus Cristi LNG deal as far as I'm aware which was from Q4 2019. Any sales agreements linked to Henry Hub will be a tiny portion of WPL's portfolio.
I expect over the next few years we'll see WPL take on a few more contracts linked to Henry Hub to match the Corpus Cristi volumes - risk management of high high Henry Hub with low oil price which would otherwise potentially cause a loss. At the moment Henry Hub has no real link to WPL.
Most long term contracts are linked to dated Brent (3 month lag to Brent oil price) but it's not a 1 to 1 ratio. Below $50-60 Brent the gradient reduces protecting the infrastructure investment from becoming uneconomic (at least in WPL's contracts shown a few years back).
Spot LNG is also often worth a look - it shows what the markets doing, it's around $10 / mmbtu.
Note: Don't look at WTI, chemically it should sell at a premium to Brent, but over supply in the US has driven down the price.
It can be a bit confusing knowing exactly which energy markets to look at. The link for WPL is largely to Brent - and WPL also does most of their commentary around Brent in reports.