Vinyl and Linoleum Flooring - Mold under vinyl/linoleum floor in bathroom

Was hoping that someone could settle an argument.

We were taking the toilet, vanity and vinyl flooring out of my inlaws bathroom. We are going to replace the flooring with ceramic tile. However, we discovered that the toilet has been leaking for some time. There are signs that mold was starting to grow under the old flooring between the concrete and vinyl. We got most of the old flooring up, but there is still some glue and thin layers of the vinyl remaining.

So here is the disagreement.

My friend says that we should just tile over whatever is left and that the mold won't be an issue.

I feel that whatever mold that could still be under what is left of the vinyl is bad. I was also thinking that the mold could use the glue and vinyl a source of "food" and could still spread. Even when we set the new toilet in place and the main source of moisture is fixed.


Any input would be welcomed.

Thanks
Gordon

thinset will not stick well, if at all, to the remaining glue/vinyl.
get it all off.

DON'T use ANY type of cleaner on the slab where the tile will set. water only.
where the tiles will not set. lets wait for someone who knows.

id remove the rest of the vinyl and glue. and if you feel like the mold is an issue. spray the floor with vinegar. I know its going to smell kinda bad. but the vinegar kills the mold. it really does work. ive done it before myself.