Non tented vias in pads are ok?

Hello,
I have put 0.3mm vias (as attached) in the pads of the SBRT25U80 Schottky diodes in the PCB that i've just layed out. (for cooling purposes)
The vias have their annulae on the bottom layer covered in solder resist. (this is to limit solder wicking down the thermal via during surface mount soldering).
We have got the 4 prototype boards manufactured now, and it cost us £1000.
However, an engineer who works at a PCB assembly place has just told me that vias in pads like this should be tented.

The boards have been manufactured now, so it’s too late to get the vias tented….so will it be ok to go ahead and get the boards populated with components without the tenting?
I mean, if tenting really is essential, then can we brush over the via openings with conformal coating?…or try and jam some conformal coating compound up the vias?
(By the way, the engineer has told us that it wouldn’t have been practical to get these vias ‘filled’ with solder)

SBRT25U80SLP Schottky datasheet:-
**broken link removed**

I think the problem of open/untented vias in pads has been discussed extensively in your previous thread https://www.edaboard.com/threads/275722/

I don't believe that "should be tented" is an appropriate answer to the complex problem. Better answers have been given e.g. by Mattylad and marce in your previous thread. I just want to add that I have designed a larger number of PCBs with similar footprints. None of it revealed production problems.

Prototype manufacturing shouldn't be a problem anyway.