Its obviously impossible to create an HDR from a single jpg. If you've got the raw files, then it could be done from that. The only way to know for sure is to have a go.
But, I was reminded of a post by HimUpNorth a while back which took a while to find, but I did - Contrast Masking - an HDR alternative:
here.
Using a similar workflow to that described by Gary in that post, I managed these 2 edits:
and
That exercise has produced what I think is a much better version of your 1st pic. As for the 2nd, I'm not so sure and it would probably take a more experienced PS person than me to sort it out. But hope that helps.
MV