Don't count on any Oligarchs investing.
UK,State dept and Treasury dept are to start sanctions on the Oligarchs close to Putin.
Quite a few articles on it today about upcoming US sanctions hitting the Oligarchs.
China and Middle East seems to be the safer bet for outside investment,it's just right now is the club high profile enough to catch their attention,the reason the Shiekh Mansour bought City is they already had a brand new stadium and the land around it in Eastlands was cheap enough to invest further into regeneration of the area to promote Mansour's country's standing.
The BMD stadium has to built first and quickly and the turnover increased exponentially (right now) as the gap with the "top 6" is growing and growing (talk recently of those 6 clubs getting a separate tv deal on international tv rights),FFP is tightening and it's harder for outside investors to do a PSG,Chelsea and City and accelerate those clubs standing quickly without falling foul of FFP now.PSG are going to be sanctioned soon for their over priced Qatar commercial deals and fiddling the books to sign Neymar and Mbappe.
The days of a sugar daddy buying a club and splurging without a care are dead in Europe,Uefa hate it (FFP 2.0 is coming),the G14 clubs hate it, you only have to see the likes of the Spanish fa boss bemoaning (after the neymar deal) what City and Psg spend and how state runs clubs should not be allowed in the CL.