Be interested to see pics. I wouldn't panic, but I would personally be inclined to call a good equine vet if the horse was lame for 2 weeks. Lameness from abscesses generally comes & go pretty suddenly. If they don't it can signify a chronic problem of which the abscess may be just a symptom of. Bruising tends to be not so acute(tho can turn into abscess too) but can go on for much longer. What concerns me is that the soles are flat & thin, you say it's still soft and there's heat in the foot. I'd want to treat any infection quickly & effectively and also rule out other possibilities such as pedal bone fracture or such.
Agree basically with what Painthorse says, that it may be no worries & normal progression, and that leaving it open to dry out is probably best. I would however be cautious of *ongoing* use of betadine or such if it's on live tissue, as it can damage & ****** new growth.
Given flat, thin soles, I would definitely be protecting his feet for work too.