I think there are a few reasons.Timing.... WGX has until...

I think there are a few reasons.
Timing.... WGX has until recently, lagged its neighbor RMS (which... is almost 100% higher MC), which has so far proved incredibly powerful in outbidding WGX for their attempt on MGV. So that could be a factor.
WGX has IMHO, been bidding their time to allow their script to be revalued to a more reasonable valuation, to allow them to them pursue deals.
Secondly, WGX has been (and in my view still is, undervalued), which would have meant any offer at SPR would be heavily dilutive to current holders (though for what it's worth, I would be more than comfortable with WGX being heavily diluted to acquire one of the best discoveries in W.A in modern times).
SPRs success has likely surprised everyone... which has seen SPR valued very highly, compared to WGX with it's almost 260k+ production profile and $250m in cash...
WGX has only recently pushed the button on two major internal growth projects, which arguably has been their major focus.
SPRs two main holders (35% of the company) are not yet interested in entertaining offers at lower prices (though I think it might have changed very recently with one major holder not replacing their board member).
WB has shown he can be prudent when they did not outbid RMS for MGV (funnily enough, WGX offer, I believe would now have rewarded MGV holders more than the RMS offer).
Could be lots of other reasons too (bigger deal like a merger between RMS/WGX etc etc).