Fitness trackers or other solutions?

Ok, so since being in lockdown I've been staying with my family and using an old static bike they have. I say old, it's a really good quality one with good resistance levels and a digital display.
Only problem of course is that I can't read the display. The bike is giving me speed, time, distance, callories burnt, all information I would like to access. I've tried envision and seeing AI to try and read the display with nothing fed back to me that I can make sense of. I do have an apple watch, even using the indoor cycling mode in the workout app, it didn't reckon I'd burnt half as many calories as the bike did. I'm guessing the bike is getting more accurate information based on my speed and resistance level which the watch isn't getting.

I've been researching fitness trackers and apps but they all measure what you've done by GPS, so great for outdoor cycling, not for indoor.

So here's my question. Does anybody have a solution to this? Either a really good different fitness tracker that would give me these stats or a better way of reading the screen on the bike that I haven't thought of?

I've even been looking at bikes with app compatibility to buy when I go home but they are all insanely expensive, and as nobody here uses the bike I've been using my family say I can take it home with me, which is awesome but I really need to be able to see my stats!

Any suggestions much appreciated, and sorry for the long post!

Thanks Applevis