Mhh, not sure why it would count the channel reserve to outbound liquidity but 1% of a channel is usually not available to spend, so this might still be the issue you're running into:

What is a channel reserve?

A channel reserve is an amount that is set aside by each channel participant which ensures neither have ‘nothing at stake’ if a cheating attempt occurs. This reserve can not be spent, and is held aside for the entirety of the channels lifetime.

Channel reserves make cheating attempts less economical. When one channel party attempts to cheat the other and they are caught, a penalty transaction can be used to steal all the cheating parties bitcoin as punishment. Channel reserves makes it so cheating attempts always have something at stake making this less likely to occur.