This is a difficult one for a number of reasons and we are in a similar position. However, I would say (at the moment) that we have been fortunate with the LA and our SW's. Everyone involved in this placement has been super positive and want to continue with introductions rather than delaying for longer (including the FC's). I picked this out from CoramBAAF regarding introductions during COVID19 as I did also raise this with them just in case they had similar ideas.
Children who are “looked after” have been defined by the Government as “vulnerable children”. The placement of a child with prospective adopter/s is a key intervention in ensuring the safety, welfare and future of the child, but the risks associated with making such placements must be identified and explicitly addressed.
Basically, it's possible and they can do something.
Whilst I understand your friend from AdoptionUk saying it won't go in your favour, I think this is really really unfair to say! You have reasonable cause should you change your mind. The child is 15months old and could be much older when they potentially move causing disruption to any attachment with a child. Facetime won't provide that.
Likewise, if you are like us, you are now committed and have started making that bond, want and desire for that particular child(ren) you will want to hold out as long as possible. But, their has to be a reasonable expectation and timeframe. Ask me again in two months and if I'm still here, I genuinely feel our position on these children maybe different (they are older).
We, as I'm sure everyone else, are self isolating. This in itself should be one of many reasonable precautions prior to introductions. I think they need to do some more thinking outside the box to make this happen, but that's my opinion I guess.