It is not against the rules for members of the House of Lords to accept remuneration for the provision of consultancy/advice to domestic or foreign businessmen - although perhaps it should be.
Nor do I see an allegation that any of the four alleged miscreants offered to table a legislative amendment (as opposed to arranging for an amendment to be tabled). A fine distinction, perhaps, but nevertheless.
Thirdly, none of the discussions appears to have progressed beyond preliminary assessments of what might be possible. No agreements were finalised, no money appears to have changed hands and there is presumably nothing in writing.
That being so, and disappointing as it may be to those of us who care about the morality (or lack of it) in the Mother of Parliaments, I fail to detect a smoking gun. And I can't see that the various promised investigations will lead anywhere.