My unsolicited advice regarding VRT and the takeover offer - take the sugar hit of +30% and jump ship.
I held VRT for many years under the thesis that a) they're the biggest, b) they have existing international operations and c) IVF is emotional meaning people pay whatever they need to to get success.
After my five years of holding, I realised it is a company with great potential, but it is run by doctors whom are not business people and so its opportunity to remain the market leader continues to erode. It pays some good dividends which propped its performance up on Sharesight reports... but ultimately I moved on.
Also, as you rightly point out, due diligence can find things that torpedo the buy out...
Disc: no longer held.