I can not confirm multiboot at froscon, have not seen and to be completely honest chen actually asked us not to reboot since there was currently an unwanted state in the test devices that let them only do 5 reboots successfull. Do not know more details though.
The only time i saw some kind of bootloader was the pure fastboot menu at the Düsseldorf event in the photo i linked pages back.

The Jolla retweet.
The "amazing guys" mentioned in the tweet are for sure Olf & Thaodan since they organised the event!

Thaodan told me he communicated with James upfront and was advised to add Photos to play by the social media rules. So he added the Photos you now see retweeted by jolla containing the Pro1.

Lets read the minimum positivity from that.
Jolla at least did not say to Thaodan "please use another image since it is way to early to associate ourselfs with fxtec in any way until they have proven themselfs".

Oh, and Jolla employees privately throwing an eye on the pro1 is another small positive detail imo

And speeking of press, i might have attracted @tonekaboni (editor at c't magazin) to look at the pro1 and he commented along the positive sentimental lines.