I'm not sure what specifically are the concerns... so I'll just say some stuff.
The brake cable port and front underside of the TT- Are the squiggly lines cracks, rust fingers or the uneven edges of the paint that's under the primer? I see no obvious tube ripples in the usual locations to suspect a front end impact. I do see some odd lump adjacent to the cable port. It could be brass filler that had gooped up there and was never fully removed during the making of this frame. Or it could be a bad Bondoing of something that's not wanted to be shown to a buyer
Have you placed a straight edge along the top tube's upper side to see if the tube is bowed, or straight? Same with the down tube.
No good views of the fork so can't say much about possible bend back from a frontal impact. The pic from above is off angle enough to not be useable as any reference for the fork being splayed to one side or the other. One view that would be good to see is from the dead on front with the fork rotated 90*, the head tube and fork blades will line up.
Can you provide more info about this frame? Looks to be a Raleigh and by the thick head badge one of the Asian ones. There were some nice models but the vast majority that most shops sold were fairly base lever examples. You mention the twitchy steering. Compared to what bike? Is there a local shop or "frame guy" that can take a look at the bike? Don't be surprised if the aligning is worth more then the bike is (if the bike is one of the basic models). Andy